diff --git a/gitutil/.api b/gitutil/.api
index c86d89c..dcd0a23 100644
--- a/gitutil/.api
+++ b/gitutil/.api
@@ -44,6 +44,7 @@
 pkg gitutil, method (*Git) Push(string, string, ...PushOpt) error
 pkg gitutil, method (*Git) Rebase(string) error
 pkg gitutil, method (*Git) RebaseAbort() error
+pkg gitutil, method (*Git) RefExistsOnBranch(string, string) bool
 pkg gitutil, method (*Git) RemoteUrl(string) (string, error)
 pkg gitutil, method (*Git) Remove(...string) error
 pkg gitutil, method (*Git) RemoveUntrackedFiles() error
diff --git a/gitutil/git.go b/gitutil/git.go
index ee77840..c6a6675 100644
--- a/gitutil/git.go
+++ b/gitutil/git.go
@@ -536,6 +536,15 @@
 	return g.run("rebase", "--abort")
 }
 
+// RefExistsOnBranch returns true if the given ref exists on the given branch.
+func (g *Git) RefExistsOnBranch(ref, branch string) bool {
+	args := []string{"merge-base", "--is-ancestor", ref, branch}
+	if err := g.run(args...); err != nil {
+		return false
+	}
+	return true
+}
+
 // Remove removes the given files.
 func (g *Git) Remove(fileNames ...string) error {
 	args := []string{"rm"}
diff --git a/project/project.go b/project/project.go
index 742d3b7..c8fbf09 100644
--- a/project/project.go
+++ b/project/project.go
@@ -1462,13 +1462,20 @@
 	}
 	switch project.Protocol {
 	case "git":
-		// Having a specific revision trumps everything else.
+		git := gitutil.New(jirix.NewSeq())
+		remoteBranch := "origin/" + project.RemoteBranch
+
+		// If a specific revision is set, make sure it exists on the specified
+		// remote branch, and reset to that revision.
 		if project.Revision != "HEAD" {
-			return gitutil.New(jirix.NewSeq()).Reset(project.Revision)
+			if !git.RefExistsOnBranch(project.Revision, remoteBranch) {
+				return fmt.Errorf("revision %q does not exist on remote branch %q", project.Revision, remoteBranch)
+			}
+			return git.Reset(project.Revision)
 		}
-		// If no revision, reset to the configured remote branch, or master
-		// if no remote branch.
-		return gitutil.New(jirix.NewSeq()).Reset("origin/" + project.RemoteBranch)
+
+		// If no revision is set, reset to the remote branch.
+		return git.Reset(remoteBranch)
 	default:
 		return UnsupportedProtocolErr(project.Protocol)
 	}
@@ -2065,10 +2072,6 @@
 		if err := s.Chdir(tmpDir).Done(); err != nil {
 			return err
 		}
-		// TODO(toddw): Why call Reset here, when resetProject is called just below?
-		if err := gitutil.New(jirix.NewSeq()).Reset(op.project.Revision); err != nil {
-			return err
-		}
 	default:
 		return UnsupportedProtocolErr(op.project.Protocol)
 	}
@@ -2193,7 +2196,7 @@
 }
 
 func (op moveOperation) String() string {
-	return fmt.Sprintf("move project %q located in %q to %q and advance it to %q", op.project.Name, op.source, op.destination, fmtRevision(op.project.Revision))
+	return fmt.Sprintf("move project %q located in %q to %q and advance it to %q of %q", op.project.Name, op.source, op.destination, fmtRevision(op.project.Revision), op.project.RemoteBranch)
 }
 
 func (op moveOperation) Test(jirix *jiri.X, updates *fsUpdates) error {
@@ -2237,7 +2240,7 @@
 }
 
 func (op updateOperation) String() string {
-	return fmt.Sprintf("advance project %q located in %q to %q", op.project.Name, op.source, fmtRevision(op.project.Revision))
+	return fmt.Sprintf("advance project %q located in %q to %q of %q", op.project.Name, op.source, fmtRevision(op.project.Revision), op.project.RemoteBranch)
 }
 
 func (op updateOperation) Test(jirix *jiri.X, _ *fsUpdates) error {
diff --git a/project/project_test.go b/project/project_test.go
index a060e36..b4c69af 100644
--- a/project/project_test.go
+++ b/project/project_test.go
@@ -172,7 +172,7 @@
 	return revision
 }
 
-// Fix the revision in the manifest file.
+// Set the revision in the manifest file.
 func setRevisionForProject(t *testing.T, jirix *jiri.X, manifestDir, name, revision string) {
 	m, err := project.ManifestFromFile(jirix, filepath.Join(manifestDir, "v2", "default"))
 	if err != nil {
@@ -188,7 +188,28 @@
 		}
 	}
 	if !updated {
-		t.Fatalf("failed to fix revision for project %v", name)
+		t.Fatalf("failed to set revision for project %v", name)
+	}
+	commitManifest(t, jirix, m, manifestDir)
+}
+
+// Set the remote branch in the manifest file.
+func setRemoteBranchForProject(t *testing.T, jirix *jiri.X, manifestDir, name, remoteBranch string) {
+	m, err := project.ManifestFromFile(jirix, filepath.Join(manifestDir, "v2", "default"))
+	if err != nil {
+		t.Fatal(err)
+	}
+	updated := false
+	for i, p := range m.Projects {
+		if p.Name == name {
+			p.RemoteBranch = remoteBranch
+			m.Projects[i] = p
+			updated = true
+			break
+		}
+	}
+	if !updated {
+		t.Fatalf("failed to fix remote branch for project %v", name)
 	}
 	commitManifest(t, jirix, m, manifestDir)
 }
@@ -523,14 +544,26 @@
 		t.Fatalf("%v", err)
 	}
 
-	// Commit to a non-master branch of a remote project and check that
-	// UpdateUniverse() can update the local project to point to a revision on
-	// that branch.
+	// Commit to master and non-master branches of a remote project.
+	nonMasterBranch := "non_master"
 	writeReadme(t, jirix, remoteProjects[5], "master commit")
-	createAndCheckoutBranch(t, jirix, remoteProjects[5], "non_master")
+	createAndCheckoutBranch(t, jirix, remoteProjects[5], nonMasterBranch)
 	writeReadme(t, jirix, remoteProjects[5], "non master commit")
 	remoteBranchRevision := currentRevision(t, jirix, remoteProjects[5])
+
+	// Set the revision to the non-master revision, but keep the remote branch
+	// set to master.
 	setRevisionForProject(t, jirix, remoteManifest, remoteProjects[5], remoteBranchRevision)
+	// Check that UpdateUniverse() fails when updating to a revision that does
+	// not occur on the remote branch (master).
+	if err := project.UpdateUniverse(jirix, true); err == nil {
+		t.Fatalf("expected project.UpdateUniverse() with revision that does not occur on remote branch to fail, but it did not")
+	}
+
+	// Set the project remote branch to the non-master branch with the revision.
+	setRemoteBranchForProject(t, jirix, remoteManifest, remoteProjects[5], nonMasterBranch)
+	// Check that UpdateUniverse() can update the local project to point to a
+	// revision on the non-master remote branch.
 	if err := project.UpdateUniverse(jirix, true); err != nil {
 		t.Fatalf("%v", err)
 	}