diff --git a/repo.go b/repo.go
index 0834cfd1..e273ad9b 100644
--- a/repo.go
+++ b/repo.go
@@ -452,7 +452,7 @@ func (r *Repo) RootKeys() ([]*data.PublicKey, error) {
 	return rootKeys(root)
 }
 
-func rootKeys(root *data.Root) ([]*data.Key, error) {
+func rootKeys(root *data.Root) ([]*data.PublicKey, error) {
 	role, ok := root.Roles["root"]
 	if !ok {
 		return nil, nil
diff --git a/repo_extended.go b/repo_extended.go
new file mode 100644
index 00000000..795bf2fa
--- /dev/null
+++ b/repo_extended.go
@@ -0,0 +1,99 @@
+package tuf
+
+import (
+	"time"
+
+	"github.com/theupdateframework/go-tuf/data"
+)
+
+func (r *Repo) IncrementRootVersion() error {
+	return r.IncrementRootVersionWithExpires(data.DefaultExpires("root"))
+}
+
+func (r *Repo) IncrementRootVersionWithExpires(expires time.Time) error {
+	role, err := r.root()
+	if err != nil {
+		return err
+	}
+
+	if !validExpires(expires) {
+		return ErrInvalidExpires{expires}
+	}
+
+	role.Expires = expires.Round(time.Second)
+	if !r.local.FileIsStaged("root.json") {
+		role.Version++
+	}
+
+	return r.setMeta("root.json", role)
+}
+
+func (r *Repo) RootExpires() (time.Time, error) {
+	role, err := r.root()
+	if err != nil {
+		return time.Time{}, err
+	}
+	return role.Expires, nil
+}
+
+func (r *Repo) IncrementSnapshotVersion() error {
+	return r.Snapshot()
+}
+
+func (r *Repo) IncrementSnapshotVersionWithExpires(expires time.Time) error {
+	return r.SnapshotWithExpires(expires)
+}
+
+func (r *Repo) SnapshotExpires() (time.Time, error) {
+	role, err := r.snapshot()
+	if err != nil {
+		return time.Time{}, err
+	}
+	return role.Expires, nil
+}
+
+func (r *Repo) IncrementTargetsVersion() error {
+	return r.IncrementTargetsVersionWithExpires(data.DefaultExpires("targets"))
+}
+
+func (r *Repo) IncrementTargetsVersionWithExpires(expires time.Time) error {
+	role, err := r.topLevelTargets()
+	if err != nil {
+		return err
+	}
+
+	if !validExpires(expires) {
+		return ErrInvalidExpires{expires}
+	}
+
+	role.Expires = expires.Round(time.Second)
+	if !r.local.FileIsStaged("targets.json") {
+		role.Version++
+	}
+
+	return r.setMeta("targets.json", role)
+}
+
+func (r *Repo) TargetsExpires() (time.Time, error) {
+	role, err := r.topLevelTargets()
+	if err != nil {
+		return time.Time{}, err
+	}
+	return role.Expires, nil
+}
+
+func (r *Repo) IncrementTimestampVersion() error {
+	return r.Timestamp()
+}
+
+func (r *Repo) IncrementTimestampVersionWithExpires(expires time.Time) error {
+	return r.TimestampWithExpires(expires)
+}
+
+func (r *Repo) TimestampExpires() (time.Time, error) {
+	role, err := r.timestamp()
+	if err != nil {
+		return time.Time{}, err
+	}
+	return role.Expires, nil
+}
diff --git a/repo_extended_test.go b/repo_extended_test.go
new file mode 100644
index 00000000..d32e4a1d
--- /dev/null
+++ b/repo_extended_test.go
@@ -0,0 +1,249 @@
+package tuf
+
+import (
+	. "gopkg.in/check.v1"
+)
+
+func genKeyErr(_ []string, err error) error {
+	return err
+}
+
+func initRepo(c *C, r *Repo, paths []string) {
+	c.Assert(r.Init(false), IsNil)
+	c.Assert(genKeyErr(r.GenKey("root")), IsNil)
+	c.Assert(genKeyErr(r.GenKey("targets")), IsNil)
+	c.Assert(genKeyErr(r.GenKey("snapshot")), IsNil)
+	c.Assert(genKeyErr(r.GenKey("timestamp")), IsNil)
+	c.Assert(r.AddTargets(paths, nil), IsNil)
+	c.Assert(r.Snapshot(CompressionTypeNone), IsNil)
+	c.Assert(r.Timestamp(), IsNil)
+	c.Assert(r.Commit(), IsNil)
+}
+
+func (RepoSuite) TestRolesExpirationsRotation(c *C) {
+	local := MemoryStore(nil, map[string][]byte{
+		"myfile": []byte("DATA\n"),
+	})
+
+	r, err := NewRepo(local)
+	c.Assert(err, IsNil)
+
+	initRepo(c, r, []string{"myfile"})
+
+	prevRootVersion, err := r.RootVersion()
+	c.Assert(err, IsNil)
+	prevRootExpires, err := r.RootExpires()
+	c.Assert(err, IsNil)
+
+	prevTargetsVersion, err := r.TargetsVersion()
+	c.Assert(err, IsNil)
+	prevTargetsExpires, err := r.TargetsExpires()
+	c.Assert(err, IsNil)
+
+	prevSnapshotVersion, err := r.SnapshotVersion()
+	c.Assert(err, IsNil)
+	prevSnapshotExpires, err := r.SnapshotExpires()
+	c.Assert(err, IsNil)
+
+	prevTimestampVersion, err := r.TimestampVersion()
+	c.Assert(err, IsNil)
+	prevTimestampExpires, err := r.TimestampExpires()
+	c.Assert(err, IsNil)
+
+	// Update timestamp
+	for i := 0; i < 10; i++ {
+		r, err := NewRepo(local)
+		c.Assert(err, IsNil)
+
+		newTimestampExpires := prevTimestampExpires.AddDate(0, 0, 1)
+
+		c.Assert(r.IncrementTimestampVersionWithExpires(newTimestampExpires), IsNil)
+		c.Assert(r.Commit(), IsNil)
+
+		root, err := r.root()
+		c.Assert(err, IsNil)
+		c.Assert(root.Version, Equals, prevRootVersion)
+		c.Assert(root.Expires, Equals, prevRootExpires)
+
+		targets, err := r.targets()
+		c.Assert(err, IsNil)
+		c.Assert(targets.Version, Equals, prevTargetsVersion)
+		c.Assert(targets.Expires, Equals, prevTargetsExpires)
+
+		snapshot, err := r.snapshot()
+		c.Assert(err, IsNil)
+		c.Assert(snapshot.Version, Equals, prevSnapshotVersion)
+		c.Assert(snapshot.Expires, Equals, prevSnapshotExpires)
+
+		timestamp, err := r.timestamp()
+		c.Assert(err, IsNil)
+		c.Assert(timestamp.Version, Equals, prevTimestampVersion+1)
+		c.Assert(timestamp.Expires, Equals, newTimestampExpires)
+		prevTimestampVersion = timestamp.Version
+		prevTimestampExpires = timestamp.Expires
+	}
+
+	// Update snapshot, depends on timestamp
+	for i := 0; i < 10; i++ {
+		r, err := NewRepo(local)
+		c.Assert(err, IsNil)
+
+		newSnapshotExpires := prevSnapshotExpires.AddDate(0, 0, 7)
+		newTimestampExpires := prevTimestampExpires.AddDate(0, 0, 1)
+
+		c.Assert(r.IncrementSnapshotVersionWithExpires(newSnapshotExpires), IsNil)
+		c.Assert(r.IncrementTimestampVersionWithExpires(newTimestampExpires), IsNil)
+		c.Assert(r.Commit(), IsNil)
+
+		root, err := r.root()
+		c.Assert(err, IsNil)
+		c.Assert(root.Version, Equals, prevRootVersion)
+		c.Assert(root.Expires, Equals, prevRootExpires)
+
+		targets, err := r.targets()
+		c.Assert(err, IsNil)
+		c.Assert(targets.Version, Equals, prevTargetsVersion)
+		c.Assert(targets.Expires, Equals, prevTargetsExpires)
+
+		snapshot, err := r.snapshot()
+		c.Assert(err, IsNil)
+		c.Assert(snapshot.Version, Equals, prevSnapshotVersion+1)
+		c.Assert(snapshot.Expires, Equals, newSnapshotExpires)
+		prevSnapshotVersion = snapshot.Version
+		prevSnapshotExpires = snapshot.Expires
+
+		timestamp, err := r.timestamp()
+		c.Assert(err, IsNil)
+		c.Assert(timestamp.Version, Equals, prevTimestampVersion+1)
+		c.Assert(timestamp.Expires, Equals, newTimestampExpires)
+		prevTimestampVersion = timestamp.Version
+		prevTimestampExpires = timestamp.Expires
+	}
+
+	// Update targets, depends on snapshot and timestamp
+	for i := 0; i < 10; i++ {
+		r, err := NewRepo(local)
+		c.Assert(err, IsNil)
+
+		newTargetsExpires := prevTargetsExpires.AddDate(0, 3, 0)
+		newSnapshotExpires := prevSnapshotExpires.AddDate(0, 0, 7)
+		newTimestampExpires := prevTimestampExpires.AddDate(0, 0, 1)
+
+		c.Assert(r.IncrementTargetsVersionWithExpires(newTargetsExpires), IsNil)
+		c.Assert(r.IncrementSnapshotVersionWithExpires(newSnapshotExpires), IsNil)
+		c.Assert(r.IncrementTimestampVersionWithExpires(newTimestampExpires), IsNil)
+		c.Assert(r.Commit(), IsNil)
+
+		root, err := r.root()
+		c.Assert(err, IsNil)
+		c.Assert(root.Version, Equals, prevRootVersion)
+		c.Assert(root.Expires, Equals, prevRootExpires)
+
+		targets, err := r.targets()
+		c.Assert(err, IsNil)
+		c.Assert(targets.Version, Equals, prevTargetsVersion+1)
+		c.Assert(targets.Expires, Equals, newTargetsExpires)
+		prevTargetsVersion = targets.Version
+		prevTargetsExpires = targets.Expires
+
+		snapshot, err := r.snapshot()
+		c.Assert(err, IsNil)
+		c.Assert(snapshot.Version, Equals, prevSnapshotVersion+1)
+		c.Assert(snapshot.Expires, Equals, newSnapshotExpires)
+		prevSnapshotVersion = snapshot.Version
+		prevSnapshotExpires = snapshot.Expires
+
+		timestamp, err := r.timestamp()
+		c.Assert(err, IsNil)
+		c.Assert(timestamp.Version, Equals, prevTimestampVersion+1)
+		c.Assert(timestamp.Expires, Equals, newTimestampExpires)
+		prevTimestampVersion = timestamp.Version
+		prevTimestampExpires = timestamp.Expires
+	}
+
+	// Update root, depends on snapshot and timestamp
+	for i := 0; i < 10; i++ {
+		r, err := NewRepo(local)
+		c.Assert(err, IsNil)
+
+		newRootExpires := prevRootExpires.AddDate(1, 0, 0)
+		newSnapshotExpires := prevSnapshotExpires.AddDate(0, 0, 7)
+		newTimestampExpires := prevTimestampExpires.AddDate(0, 0, 1)
+
+		c.Assert(r.IncrementRootVersionWithExpires(newRootExpires), IsNil)
+		c.Assert(r.IncrementSnapshotVersionWithExpires(newSnapshotExpires), IsNil)
+		c.Assert(r.IncrementTimestampVersionWithExpires(newTimestampExpires), IsNil)
+		c.Assert(r.Commit(), IsNil)
+
+		root, err := r.root()
+		c.Assert(err, IsNil)
+		c.Assert(root.Version, Equals, prevRootVersion+1)
+		c.Assert(root.Expires, Equals, newRootExpires)
+		prevRootVersion = root.Version
+		prevRootExpires = root.Expires
+
+		targets, err := r.targets()
+		c.Assert(err, IsNil)
+		c.Assert(targets.Version, Equals, prevTargetsVersion)
+		c.Assert(targets.Expires, Equals, prevTargetsExpires)
+
+		snapshot, err := r.snapshot()
+		c.Assert(err, IsNil)
+		c.Assert(snapshot.Version, Equals, prevSnapshotVersion+1)
+		c.Assert(snapshot.Expires, Equals, newSnapshotExpires)
+		prevSnapshotVersion = snapshot.Version
+		prevSnapshotExpires = snapshot.Expires
+
+		timestamp, err := r.timestamp()
+		c.Assert(err, IsNil)
+		c.Assert(timestamp.Version, Equals, prevTimestampVersion+1)
+		c.Assert(timestamp.Expires, Equals, newTimestampExpires)
+		prevTimestampVersion = timestamp.Version
+		prevTimestampExpires = timestamp.Expires
+	}
+
+	// Update root, targets, snapshot and timestamp at the same time
+	for i := 0; i < 10; i++ {
+		r, err := NewRepo(local)
+		c.Assert(err, IsNil)
+
+		newRootExpires := prevRootExpires.AddDate(1, 0, 0)
+		newTargetsExpires := prevTargetsExpires.AddDate(0, 3, 0)
+		newSnapshotExpires := prevSnapshotExpires.AddDate(0, 0, 7)
+		newTimestampExpires := prevTimestampExpires.AddDate(0, 0, 1)
+
+		c.Assert(r.IncrementRootVersionWithExpires(newRootExpires), IsNil)
+		c.Assert(r.IncrementTargetsVersionWithExpires(newTargetsExpires), IsNil)
+		c.Assert(r.IncrementSnapshotVersionWithExpires(newSnapshotExpires), IsNil)
+		c.Assert(r.IncrementTimestampVersionWithExpires(newTimestampExpires), IsNil)
+		c.Assert(r.Commit(), IsNil)
+
+		root, err := r.root()
+		c.Assert(err, IsNil)
+		c.Assert(root.Version, Equals, prevRootVersion+1)
+		c.Assert(root.Expires, Equals, newRootExpires)
+		prevRootVersion = root.Version
+		prevRootExpires = root.Expires
+
+		targets, err := r.targets()
+		c.Assert(err, IsNil)
+		c.Assert(targets.Version, Equals, prevTargetsVersion+1)
+		c.Assert(targets.Expires, Equals, newTargetsExpires)
+		prevTargetsVersion = targets.Version
+		prevTargetsExpires = targets.Expires
+
+		snapshot, err := r.snapshot()
+		c.Assert(err, IsNil)
+		c.Assert(snapshot.Version, Equals, prevSnapshotVersion+1)
+		c.Assert(snapshot.Expires, Equals, newSnapshotExpires)
+		prevSnapshotVersion = snapshot.Version
+		prevSnapshotExpires = snapshot.Expires
+
+		timestamp, err := r.timestamp()
+		c.Assert(err, IsNil)
+		c.Assert(timestamp.Version, Equals, prevTimestampVersion+1)
+		c.Assert(timestamp.Expires, Equals, newTimestampExpires)
+		prevTimestampVersion = timestamp.Version
+		prevTimestampExpires = timestamp.Expires
+	}
+}