diff --git a/ivy/src/main/scala/sbt/Ivy.scala b/ivy/src/main/scala/sbt/Ivy.scala
index 7f54fb4b4..78c8e3b99 100644
--- a/ivy/src/main/scala/sbt/Ivy.scala
+++ b/ivy/src/main/scala/sbt/Ivy.scala
@@ -4,6 +4,7 @@
 package sbt
 
 import Resolver.PluginPattern
+import ivyint.{ ConsolidatedResolveEngine, ConsolidatedResolveCache }
 
 import java.io.File
 import java.net.URI
@@ -14,12 +15,14 @@ import CS.singleton
 import org.apache.ivy.Ivy
 import org.apache.ivy.core.{ IvyPatternHelper, LogOptions }
 import org.apache.ivy.core.cache.{ CacheMetadataOptions, DefaultRepositoryCacheManager, ModuleDescriptorWriter }
+import org.apache.ivy.core.event.EventManager
 import org.apache.ivy.core.module.descriptor.{ Artifact => IArtifact, DefaultArtifact, DefaultDependencyArtifactDescriptor, MDArtifact }
 import org.apache.ivy.core.module.descriptor.{ DefaultDependencyDescriptor, DefaultModuleDescriptor, DependencyDescriptor, ModuleDescriptor, License }
 import org.apache.ivy.core.module.descriptor.{ OverrideDependencyDescriptorMediator }
 import org.apache.ivy.core.module.id.{ ArtifactId, ModuleId, ModuleRevisionId }
-import org.apache.ivy.core.resolve.{ IvyNode, ResolveData, ResolvedModuleRevision }
+import org.apache.ivy.core.resolve.{ IvyNode, ResolveData, ResolvedModuleRevision, ResolveEngine }
 import org.apache.ivy.core.settings.IvySettings
+import org.apache.ivy.core.sort.SortEngine
 import org.apache.ivy.plugins.latest.LatestRevisionStrategy
 import org.apache.ivy.plugins.matcher.PatternMatcher
 import org.apache.ivy.plugins.parser.m2.PomModuleDescriptorParser
@@ -28,6 +31,7 @@ import org.apache.ivy.util.{ Message, MessageLogger }
 import org.apache.ivy.util.extendable.ExtendableItem
 
 import scala.xml.{ NodeSeq, Text }
+import scala.collection.mutable
 
 final class IvySbt(val configuration: IvyConfiguration) {
   import configuration.baseDirectory
@@ -76,7 +80,23 @@ final class IvySbt(val configuration: IvyConfiguration) {
     }
   private lazy val ivy: Ivy =
     {
-      val i = new Ivy() { private val loggerEngine = new SbtMessageLoggerEngine; override def getLoggerEngine = loggerEngine }
+      val i = new Ivy() {
+        private val loggerEngine = new SbtMessageLoggerEngine
+        override def getLoggerEngine = loggerEngine
+        override def bind(): Unit = {
+          val prOpt = Option(getSettings.getResolver(ProjectResolver.InterProject)) map { case pr: ProjectResolver => pr }
+          // We inject the deps we need before we can hook our resolve engine.
+          setSortEngine(new SortEngine(getSettings))
+          setEventManager(new EventManager())
+          if (configuration.updateOptions.consolidatedResolution) {
+            setResolveEngine(new ResolveEngine(getSettings, getEventManager, getSortEngine) with ConsolidatedResolveEngine {
+              val consolidatedResolveCache = IvySbt.consolidatedResolveCache
+              val projectResolver = prOpt
+            })
+          } else setResolveEngine(new ResolveEngine(getSettings, getEventManager, getSortEngine))
+          super.bind()
+        }
+      }
       i.setSettings(settings)
       i.bind()
       i.getLoggerEngine.pushLogger(new IvyLoggerInterface(configuration.log))
@@ -103,6 +123,18 @@ final class IvySbt(val configuration: IvyConfiguration) {
       }
     }
 
+  /**
+   * Cleans consolidated resolution cache.
+   * @param md - module descriptor of the original Ivy graph.
+   */
+  private[sbt] def cleanConsolidatedResolutionCache(md: ModuleDescriptor, log: Logger): Unit =
+    withIvy(log) { i =>
+      val prOpt = Option(i.getSettings.getResolver(ProjectResolver.InterProject)) map { case pr: ProjectResolver => pr }
+      if (configuration.updateOptions.consolidatedResolution) {
+        IvySbt.consolidatedResolveCache.clean(md, prOpt)
+      }
+    }
+
   final class Module(rawModuleSettings: ModuleSettings) {
     val moduleSettings: ModuleSettings = IvySbt.substituteCross(rawModuleSettings)
     def owner = IvySbt.this
@@ -204,6 +236,7 @@ private object IvySbt {
   val DefaultIvyFilename = "ivy.xml"
   val DefaultMavenFilename = "pom.xml"
   val DefaultChecksums = Seq("sha1", "md5")
+  private[sbt] val consolidatedResolveCache: ConsolidatedResolveCache = new ConsolidatedResolveCache()
 
   def defaultIvyFile(project: File) = new File(project, DefaultIvyFilename)
   def defaultIvyConfiguration(project: File) = new File(project, DefaultIvyConfigFilename)
diff --git a/ivy/src/main/scala/sbt/IvyActions.scala b/ivy/src/main/scala/sbt/IvyActions.scala
index bdbf5fe1c..4960c9a2d 100644
--- a/ivy/src/main/scala/sbt/IvyActions.scala
+++ b/ivy/src/main/scala/sbt/IvyActions.scala
@@ -59,6 +59,15 @@ object IvyActions {
     iv.getSettings.getRepositoryCacheManagers.foreach(_.clean())
   }
 
+  /**
+   * Cleans the consolidated resolution cache, if any.
+   * This is called by clean.
+   */
+  private[sbt] def cleanConsolidatedResolutionCache(module: IvySbt#Module, log: Logger): Unit =
+    module.withModule(log) { (ivy, md, default) =>
+      module.owner.cleanConsolidatedResolutionCache(md, log)
+    }
+
   /** Creates a Maven pom from the given Ivy configuration*/
   def makePom(module: IvySbt#Module, configuration: MakePomConfiguration, log: Logger) {
     import configuration.{ allRepositories, moduleInfo, configurations, extra, file, filterRepositories, process, includeTypes }
diff --git a/ivy/src/main/scala/sbt/IvyConfigurations.scala b/ivy/src/main/scala/sbt/IvyConfigurations.scala
index 93025e2d7..b3e1dba1b 100644
--- a/ivy/src/main/scala/sbt/IvyConfigurations.scala
+++ b/ivy/src/main/scala/sbt/IvyConfigurations.scala
@@ -16,27 +16,42 @@ sealed trait IvyConfiguration {
   def baseDirectory: File
   def log: Logger
   def withBase(newBaseDirectory: File): This
+  def updateOptions: UpdateOptions
 }
 final class InlineIvyConfiguration(val paths: IvyPaths, val resolvers: Seq[Resolver], val otherResolvers: Seq[Resolver],
     val moduleConfigurations: Seq[ModuleConfiguration], val localOnly: Boolean, val lock: Option[xsbti.GlobalLock],
-    val checksums: Seq[String], val resolutionCacheDir: Option[File], val log: Logger) extends IvyConfiguration {
-  @deprecated("Use the variant that accepts the resolution cache location.", "0.13.0")
+    val checksums: Seq[String], val resolutionCacheDir: Option[File], val updateOptions: UpdateOptions,
+    val log: Logger) extends IvyConfiguration {
+  @deprecated("Use the variant that accepts resolutionCacheDir and updateOptions.", "0.13.0")
   def this(paths: IvyPaths, resolvers: Seq[Resolver], otherResolvers: Seq[Resolver],
     moduleConfigurations: Seq[ModuleConfiguration], localOnly: Boolean, lock: Option[xsbti.GlobalLock],
     checksums: Seq[String], log: Logger) =
-    this(paths, resolvers, otherResolvers, moduleConfigurations, localOnly, lock, checksums, None, log)
+    this(paths, resolvers, otherResolvers, moduleConfigurations, localOnly, lock, checksums, None, UpdateOptions(), log)
+
+  @deprecated("Use the variant that accepts updateOptions.", "0.13.6")
+  def this(paths: IvyPaths, resolvers: Seq[Resolver], otherResolvers: Seq[Resolver],
+    moduleConfigurations: Seq[ModuleConfiguration], localOnly: Boolean, lock: Option[xsbti.GlobalLock],
+    checksums: Seq[String], resolutionCacheDir: Option[File], log: Logger) =
+    this(paths, resolvers, otherResolvers, moduleConfigurations, localOnly, lock, checksums, resolutionCacheDir, UpdateOptions(), log)
 
   type This = InlineIvyConfiguration
   def baseDirectory = paths.baseDirectory
-  def withBase(newBase: File) = new InlineIvyConfiguration(paths.withBase(newBase), resolvers, otherResolvers, moduleConfigurations, localOnly, lock, checksums, resolutionCacheDir, log)
-  def changeResolvers(newResolvers: Seq[Resolver]) = new InlineIvyConfiguration(paths, newResolvers, otherResolvers, moduleConfigurations, localOnly, lock, checksums, resolutionCacheDir, log)
+  def withBase(newBase: File) = new InlineIvyConfiguration(paths.withBase(newBase), resolvers, otherResolvers, moduleConfigurations, localOnly, lock, checksums,
+    resolutionCacheDir, updateOptions, log)
+  def changeResolvers(newResolvers: Seq[Resolver]) = new InlineIvyConfiguration(paths, newResolvers, otherResolvers, moduleConfigurations, localOnly, lock, checksums,
+    resolutionCacheDir, updateOptions, log)
 }
-final class ExternalIvyConfiguration(val baseDirectory: File, val uri: URI, val lock: Option[xsbti.GlobalLock], val extraResolvers: Seq[Resolver], val log: Logger) extends IvyConfiguration {
+final class ExternalIvyConfiguration(val baseDirectory: File, val uri: URI, val lock: Option[xsbti.GlobalLock],
+    val extraResolvers: Seq[Resolver], val updateOptions: UpdateOptions, val log: Logger) extends IvyConfiguration {
+  @deprecated("Use the variant that accepts updateOptions.", "0.13.6")
+  def this(baseDirectory: File, uri: URI, lock: Option[xsbti.GlobalLock], extraResolvers: Seq[Resolver], log: Logger) =
+    this(baseDirectory, uri, lock, extraResolvers, UpdateOptions(), log)
+
   type This = ExternalIvyConfiguration
   def withBase(newBase: File) = new ExternalIvyConfiguration(newBase, uri, lock, extraResolvers, log)
 }
 object ExternalIvyConfiguration {
-  def apply(baseDirectory: File, file: File, lock: Option[xsbti.GlobalLock], log: Logger) = new ExternalIvyConfiguration(baseDirectory, file.toURI, lock, Nil, log)
+  def apply(baseDirectory: File, file: File, lock: Option[xsbti.GlobalLock], log: Logger) = new ExternalIvyConfiguration(baseDirectory, file.toURI, lock, Nil, UpdateOptions(), log)
 }
 
 object IvyConfiguration {
diff --git a/ivy/src/main/scala/sbt/ProjectResolver.scala b/ivy/src/main/scala/sbt/ProjectResolver.scala
index 92fa48bfe..a51e0abb8 100644
--- a/ivy/src/main/scala/sbt/ProjectResolver.scala
+++ b/ivy/src/main/scala/sbt/ProjectResolver.scala
@@ -34,6 +34,8 @@ class ProjectResolver(name: String, map: Map[ModuleRevisionId, ModuleDescriptor]
       map get revisionId map constructResult
     }
 
+  private[sbt] def getModuleDescriptor(revisionId: ModuleRevisionId): Option[ModuleDescriptor] = map.get(revisionId)
+
   def report(revisionId: ModuleRevisionId): MetadataArtifactDownloadReport =
     {
       val artifact = DefaultArtifact.newIvyArtifact(revisionId, new Date)
@@ -87,3 +89,7 @@ class ProjectResolver(name: String, map: Map[ModuleRevisionId, ModuleDescriptor]
   def setSettings(settings: ResolverSettings) { this.settings = Some(settings) }
   def getRepositoryCacheManager = settings match { case Some(s) => s.getDefaultRepositoryCacheManager; case None => sys.error("No settings defined for ProjectResolver") }
 }
+
+object ProjectResolver {
+  private[sbt] val InterProject = "inter-project"
+}
diff --git a/ivy/src/main/scala/sbt/UpdateOptions.scala b/ivy/src/main/scala/sbt/UpdateOptions.scala
new file mode 100644
index 000000000..acea391f7
--- /dev/null
+++ b/ivy/src/main/scala/sbt/UpdateOptions.scala
@@ -0,0 +1,27 @@
+package sbt
+
+import java.io.File
+
+/**
+ * Represents configurable options for update task.
+ * While UpdateConfiguration is passed into update at runtime,
+ * UpdateOption is intended to be used while setting up the Ivy object.
+ *
+ * See also UpdateConfiguration in IvyActions.scala.
+ */
+final class UpdateOptions(
+    /** If set to true, use consolidated resolution. */
+    val consolidatedResolution: Boolean) {
+
+  def withConsolidatedResolution(consolidatedResolution: Boolean): UpdateOptions =
+    copy(consolidatedResolution = consolidatedResolution)
+
+  private[sbt] def copy(
+    consolidatedResolution: Boolean = this.consolidatedResolution): UpdateOptions =
+    new UpdateOptions(consolidatedResolution)
+}
+
+object UpdateOptions {
+  def apply(): UpdateOptions =
+    new UpdateOptions(false)
+}
diff --git a/ivy/src/main/scala/sbt/ivyint/ConsolidatedResolveEngine.scala b/ivy/src/main/scala/sbt/ivyint/ConsolidatedResolveEngine.scala
new file mode 100644
index 000000000..c853791c8
--- /dev/null
+++ b/ivy/src/main/scala/sbt/ivyint/ConsolidatedResolveEngine.scala
@@ -0,0 +1,120 @@
+package sbt
+package ivyint
+
+import java.io.File
+import collection.concurrent
+import org.apache.ivy.core
+import core.resolve._
+import core.module.id.ModuleRevisionId
+import core.report.ResolveReport
+import core.module.descriptor.{ DefaultModuleDescriptor, ModuleDescriptor, DependencyDescriptor }
+import core.{ IvyPatternHelper, LogOptions }
+import org.apache.ivy.util.Message
+
+private[sbt] object ConsolidatedResolveCache {
+  def createID(organization: String, name: String, revision: String) =
+    ModuleRevisionId.newInstance(organization, name, revision)
+  def sbtOrgTemp = "org.scala-sbt.temp"
+}
+
+private[sbt] class ConsolidatedResolveCache() {
+  import ConsolidatedResolveCache._
+  val resolveReportCache: concurrent.Map[ModuleRevisionId, ResolveReport] = concurrent.TrieMap()
+  val resolvePropertiesCache: concurrent.Map[ModuleRevisionId, String] = concurrent.TrieMap()
+  val directDependencyCache: concurrent.Map[ModuleDescriptor, Vector[DependencyDescriptor]] = concurrent.TrieMap()
+
+  def clean(md0: ModuleDescriptor, prOpt: Option[ProjectResolver]): Unit = {
+    val mrid0 = md0.getModuleRevisionId
+    val md1 = if (mrid0.getOrganisation == sbtOrgTemp) md0
+    else buildConsolidatedModuleDescriptor(md0, prOpt)
+    val mrid1 = md1.getModuleRevisionId
+    resolveReportCache.remove(mrid1)
+    resolvePropertiesCache.remove(mrid1)
+  }
+
+  def directDependencies(md0: ModuleDescriptor): Vector[DependencyDescriptor] =
+    directDependencyCache.getOrElseUpdate(md0, md0.getDependencies.toVector)
+
+  def buildConsolidatedModuleDescriptor(md0: ModuleDescriptor, prOpt: Option[ProjectResolver]): DefaultModuleDescriptor = {
+    def expandInternalDeps(dep: DependencyDescriptor): Vector[DependencyDescriptor] =
+      prOpt map {
+        _.getModuleDescriptor(dep.getDependencyRevisionId) match {
+          case Some(internal) => directDependencies(internal) flatMap expandInternalDeps
+          case _              => Vector(dep)
+        }
+      } getOrElse Vector(dep)
+    val expanded = directDependencies(md0) flatMap expandInternalDeps
+    val depStrings = expanded map { dep =>
+      val mrid = dep.getDependencyRevisionId
+      val confMap = (dep.getModuleConfigurations map { conf =>
+        conf + "->(" + dep.getDependencyConfigurations(conf).mkString(",") + ")"
+      })
+      mrid.toString + ";" + confMap.mkString(";")
+    }
+    val depsString = depStrings.distinct.sorted.mkString("\n")
+    val sha1 = Hash.toHex(Hash(depsString))
+    // println("sha1: " + sha1)
+    val md1 = new DefaultModuleDescriptor(createID(sbtOrgTemp, "temp-resolve-" + sha1, "1.0"), "release", null, false)
+    md1
+  }
+}
+
+private[sbt] trait ConsolidatedResolveEngine extends ResolveEngine {
+  import ConsolidatedResolveCache._
+
+  private[sbt] def consolidatedResolveCache: ConsolidatedResolveCache
+  private[sbt] def projectResolver: Option[ProjectResolver]
+
+  /**
+   * Resolve dependencies of a module described by a module descriptor.
+   */
+  override def resolve(md0: ModuleDescriptor, options0: ResolveOptions): ResolveReport = {
+    val cache = consolidatedResolveCache
+    val cacheManager = getSettings.getResolutionCacheManager
+    val md1 = cache.buildConsolidatedModuleDescriptor(md0, projectResolver)
+    val md1mrid = md1.getModuleRevisionId
+
+    def doWork: (ResolveReport, String) = {
+      if (options0.getLog != LogOptions.LOG_QUIET) {
+        Message.info("Consolidating managed dependencies to " + md1mrid.toString + " ...")
+      }
+      md1.setLastModified(System.currentTimeMillis)
+      for {
+        x <- md0.getConfigurations
+      } yield md1.addConfiguration(x)
+
+      for {
+        x <- md0.getDependencies
+      } yield md1.addDependency(x)
+
+      val options1 = new ResolveOptions(options0)
+      options1.setOutputReport(false)
+      val report0 = super.resolve(md1, options1)
+      val ivyPropertiesInCache1 = cacheManager.getResolvedIvyPropertiesInCache(md1.getResolvedModuleRevisionId)
+      val prop0 =
+        if (ivyPropertiesInCache1.exists) IO.read(ivyPropertiesInCache1)
+        else ""
+      if (options0.isOutputReport) {
+        this.outputReport(report0, cacheManager, options0)
+      }
+      cache.resolveReportCache(md1mrid) = report0
+      cache.resolvePropertiesCache(md1mrid) = prop0
+      (report0, prop0)
+    }
+
+    val (report0, prop0) = (cache.resolveReportCache.get(md1mrid), cache.resolvePropertiesCache.get(md1mrid)) match {
+      case (Some(report), Some(prop)) =>
+        if (options0.getLog != LogOptions.LOG_QUIET) {
+          Message.info("Found consolidated dependency " + md1mrid.toString + " ...")
+        }
+        (report, prop)
+      case _ => doWork
+    }
+    cacheManager.saveResolvedModuleDescriptor(md0)
+    if (prop0 != "") {
+      val ivyPropertiesInCache0 = cacheManager.getResolvedIvyPropertiesInCache(md0.getResolvedModuleRevisionId)
+      IO.write(ivyPropertiesInCache0, prop0)
+    }
+    report0
+  }
+}
diff --git a/main/src/main/scala/sbt/Defaults.scala b/main/src/main/scala/sbt/Defaults.scala
index fd84d7c94..fa13a0df2 100755
--- a/main/src/main/scala/sbt/Defaults.scala
+++ b/main/src/main/scala/sbt/Defaults.scala
@@ -108,7 +108,8 @@ object Defaults extends BuildCommon {
       pomExtra :== NodeSeq.Empty,
       pomPostProcess :== idFun,
       pomAllRepositories :== false,
-      pomIncludeRepository :== Classpaths.defaultRepositoryFilter
+      pomIncludeRepository :== Classpaths.defaultRepositoryFilter,
+      updateOptions := UpdateOptions()
     )
 
   /** Core non-plugin settings for sbt builds.  These *must* be on every build or the sbt engine will fail to run at all. */
@@ -218,7 +219,11 @@ object Defaults extends BuildCommon {
       sbt.inc.ClassfileManager.transactional(crossTarget.value / "classes.bak", sbt.Logger.Null)),
     scalaInstance <<= scalaInstanceTask,
     crossVersion := (if (crossPaths.value) CrossVersion.binary else CrossVersion.Disabled),
-    crossTarget := makeCrossTarget(target.value, scalaBinaryVersion.value, sbtBinaryVersion.value, sbtPlugin.value, crossPaths.value)
+    crossTarget := makeCrossTarget(target.value, scalaBinaryVersion.value, sbtBinaryVersion.value, sbtPlugin.value, crossPaths.value),
+    clean := {
+      val _ = clean.value
+      IvyActions.cleanConsolidatedResolutionCache(ivyModule.value, streams.value.log)
+    }
   )
   // must be a val: duplication detected by object identity
   private[this] lazy val compileBaseGlobal: Seq[Setting[_]] = globalDefaults(Seq(
@@ -1075,6 +1080,7 @@ object Classpaths {
     projectID <<= pluginProjectID,
     projectDescriptors <<= depMap,
     updateConfiguration := new UpdateConfiguration(retrieveConfiguration.value, false, ivyLoggingLevel.value),
+    updateOptions := (updateOptions in Global).value,
     retrieveConfiguration := { if (retrieveManaged.value) Some(new RetrieveConfiguration(managedDirectory.value, retrievePattern.value)) else None },
     ivyConfiguration <<= mkIvyConfiguration,
     ivyConfigurations := {
@@ -1162,7 +1168,8 @@ object Classpaths {
       val explicit = buildStructure.value.units(thisProjectRef.value.build).unit.plugins.pluginData.resolvers
       explicit orElse bootRepositories(appConfiguration.value) getOrElse externalResolvers.value
     },
-    ivyConfiguration := new InlineIvyConfiguration(ivyPaths.value, externalResolvers.value, Nil, Nil, offline.value, Option(lock(appConfiguration.value)), checksums.value, Some(target.value / "resolution-cache"), streams.value.log),
+    ivyConfiguration := new InlineIvyConfiguration(ivyPaths.value, externalResolvers.value, Nil, Nil, offline.value, Option(lock(appConfiguration.value)),
+      checksums.value, Some(target.value / "resolution-cache"), UpdateOptions(), streams.value.log),
     ivySbt <<= ivySbt0,
     classifiersModule <<= (projectID, sbtDependency, transitiveClassifiers, loadedBuild, thisProjectRef) map { (pid, sbtDep, classifiers, lb, ref) =>
       val pluginClasspath = lb.units(ref.build).unit.plugins.fullClasspath
@@ -1312,7 +1319,7 @@ object Classpaths {
 
   def projectResolverTask: Initialize[Task[Resolver]] =
     projectDescriptors map { m =>
-      new RawRepository(new ProjectResolver("inter-project", m))
+      new RawRepository(new ProjectResolver(ProjectResolver.InterProject, m))
     }
 
   def analyzed[T](data: T, analysis: inc.Analysis) = Attributed.blank(data).put(Keys.analysis, analysis)
@@ -1340,11 +1347,13 @@ object Classpaths {
   def unmanagedDependencies: Initialize[Task[Classpath]] =
     (thisProjectRef, configuration, settingsData, buildDependencies) flatMap unmanagedDependencies0
   def mkIvyConfiguration: Initialize[Task[IvyConfiguration]] =
-    (fullResolvers, ivyPaths, otherResolvers, moduleConfigurations, offline, checksums in update, appConfiguration, target, streams) map { (rs, paths, other, moduleConfs, off, check, app, t, s) =>
-      warnResolversConflict(rs ++: other, s.log)
-      val resCacheDir = t / "resolution-cache"
-      new InlineIvyConfiguration(paths, rs, other, moduleConfs, off, Option(lock(app)), check, Some(resCacheDir), s.log)
-    }
+    (fullResolvers, ivyPaths, otherResolvers, moduleConfigurations, offline, checksums in update, appConfiguration,
+      target, updateOptions, streams) map { (rs, paths, other, moduleConfs, off, check, app, t, uo, s) =>
+        warnResolversConflict(rs ++: other, s.log)
+        val resCacheDir = t / "resolution-cache"
+
+        new InlineIvyConfiguration(paths, rs, other, moduleConfs, off, Option(lock(app)), check, Some(resCacheDir), uo, s.log)
+      }
 
   import java.util.LinkedHashSet
   import collection.JavaConversions.asScalaSet
@@ -1648,13 +1657,13 @@ trait BuildExtra extends BuildCommon {
     externalIvySettingsURI(Def.value(url.toURI), addMultiResolver)
   def externalIvySettingsURI(uri: Initialize[URI], addMultiResolver: Boolean = true): Setting[Task[IvyConfiguration]] =
     {
-      val other = (baseDirectory, appConfiguration, projectResolver, streams).identityMap
+      val other = (baseDirectory, appConfiguration, projectResolver, updateOptions, streams).identityMap
       ivyConfiguration <<= (uri zipWith other) {
         case (u, otherTask) =>
           otherTask map {
-            case (base, app, pr, s) =>
+            case (base, app, pr, uo, s) =>
               val extraResolvers = if (addMultiResolver) pr :: Nil else Nil
-              new ExternalIvyConfiguration(base, u, Option(lock(app)), extraResolvers, s.log)
+              new ExternalIvyConfiguration(base, u, Option(lock(app)), extraResolvers, uo, s.log)
           }
       }
     }
diff --git a/main/src/main/scala/sbt/Keys.scala b/main/src/main/scala/sbt/Keys.scala
index 41f010aef..a8e612673 100644
--- a/main/src/main/scala/sbt/Keys.scala
+++ b/main/src/main/scala/sbt/Keys.scala
@@ -242,6 +242,7 @@ object Keys {
   val moduleSettings = TaskKey[ModuleSettings]("module-settings", "Module settings, which configure dependency management for a specific module, such as a project.", DTask)
   val unmanagedBase = SettingKey[File]("unmanaged-base", "The default directory for manually managed libraries.", ASetting)
   val updateConfiguration = SettingKey[UpdateConfiguration]("update-configuration", "Configuration for resolving and retrieving managed dependencies.", DSetting)
+  val updateOptions = SettingKey[UpdateOptions]("update-options", "Options for resolving managed dependencies.", DSetting)
   val ivySbt = TaskKey[IvySbt]("ivy-sbt", "Provides the sbt interface to Ivy.", CTask)
   val ivyModule = TaskKey[IvySbt#Module]("ivy-module", "Provides the sbt interface to a configured Ivy module.", CTask)
   val updateCacheName = TaskKey[String]("updateCacheName", "Defines the directory name used to store the update cache files (inside the streams cacheDirectory).", DTask)
diff --git a/notes/0.13.6.md b/notes/0.13.6.md
new file mode 100644
index 000000000..8f98f13be
--- /dev/null
+++ b/notes/0.13.6.md
@@ -0,0 +1,10 @@
+  [413]: https://github.com/sbt/sbt/issues/413
+  [1454]: https://github.com/sbt/sbt/pull/1454
+
+### Consolidated resolution
+
+sbt 0.13.6 adds a new setting key called `updateOptions`, which can be used to enable consolidated resolution for `update` task.
+
+    updateOptions := updateOptions.value.withConsolidatedResolution(true)
+
+This feature is specifically targeted to address [Ivy resolution is beging slow for multi-module projects #413][413]. Consolidated resolution aims to fix this issue by artificially constructing an Ivy dependency graph for the unique managed dependencies. If two subprojects introduce identical external dependencies, both subprojects should consolidate to the same graph, and therefore resolve immediately for the second `update`. [#1454][1454]
diff --git a/notes/about.md b/notes/about.md
new file mode 100644
index 000000000..aedb2df72
--- /dev/null
+++ b/notes/about.md
@@ -0,0 +1 @@
+[sbt](http://www.scala-sbt.org/) is the interactive build tool.
diff --git a/sbt/src/sbt-test/dependency-management/consolidated-resolution/a/A.java b/sbt/src/sbt-test/dependency-management/consolidated-resolution/a/A.java
new file mode 100644
index 000000000..c7167d0da
--- /dev/null
+++ b/sbt/src/sbt-test/dependency-management/consolidated-resolution/a/A.java
@@ -0,0 +1,3 @@
+public class A {
+  public static final int x = 3;
+}
diff --git a/sbt/src/sbt-test/dependency-management/consolidated-resolution/c/C.java b/sbt/src/sbt-test/dependency-management/consolidated-resolution/c/C.java
new file mode 100644
index 000000000..6a053f0c1
--- /dev/null
+++ b/sbt/src/sbt-test/dependency-management/consolidated-resolution/c/C.java
@@ -0,0 +1,5 @@
+public final class C {
+  public static void main(String[] args) {
+    System.out.println(A.x);
+  }
+}
diff --git a/sbt/src/sbt-test/dependency-management/consolidated-resolution/multi.sbt b/sbt/src/sbt-test/dependency-management/consolidated-resolution/multi.sbt
new file mode 100644
index 000000000..a65418463
--- /dev/null
+++ b/sbt/src/sbt-test/dependency-management/consolidated-resolution/multi.sbt
@@ -0,0 +1,43 @@
+lazy val check = taskKey[Unit]("Runs the check")
+
+def commonSettings: Seq[Def.Setting[_]] =
+  Seq(
+    ivyPaths := new IvyPaths( (baseDirectory in ThisBuild).value, Some((target in LocalRootProject).value / "ivy-cache")),
+    libraryDependencies := Seq("net.sf.json-lib" % "json-lib" % "2.4" classifier "jdk15" intransitive()),
+    autoScalaLibrary := false, // avoid downloading fresh scala-library/scala-compiler
+    managedScalaInstance := false,
+    updateOptions := updateOptions.value.withConsolidatedResolution(true)
+  )
+lazy val root = (project in file(".")).settings(
+  organization in ThisBuild := "org.example",
+  version in ThisBuild := "1.0"
+)
+
+lazy val a = project.
+  settings(commonSettings: _*).
+  settings(
+    artifact in (Compile, packageBin) := Artifact("demo")
+  )
+
+lazy val b = project.
+  settings(commonSettings: _*).
+  settings(
+    check := {
+      val report = update.value
+      val configurationReport = (report.configurations find {_.configuration == "compile"}).head
+      val x = configurationReport.modules match {
+        case Seq(moduleReport) =>
+          moduleReport.module match {
+            case ModuleID("net.sf.json-lib", "json-lib", "2.4", _, _, _, _, _, _, _, _) => ()
+            case x => sys.error("Unexpected module: " + x.toString)
+          }
+        case x => sys.error("Unexpected modules: "  + x.toString)
+      }
+    }
+  )
+
+lazy val c = project.
+  settings(commonSettings: _*).
+  settings(
+    libraryDependencies := Seq(organization.value %% "a" % version.value)
+  )
diff --git a/sbt/src/sbt-test/dependency-management/consolidated-resolution/test b/sbt/src/sbt-test/dependency-management/consolidated-resolution/test
new file mode 100644
index 000000000..d70bd76aa
--- /dev/null
+++ b/sbt/src/sbt-test/dependency-management/consolidated-resolution/test
@@ -0,0 +1,5 @@
+> a/publishLocal
+
+> b/check
+
+> c/run