diff --git a/jsm.go b/jsm.go
index 0c3ee2978..94547e944 100644
--- a/jsm.go
+++ b/jsm.go
@@ -795,7 +795,10 @@ func (js *js) getMsg(name string, mreq *apiMsgGetRequest, opts ...JSOpt) (*RawSt
 		return nil, err
 	}
 	if resp.Error != nil {
-		return nil, errors.New(resp.Error.Description)
+		if resp.Error.Code == 404 && strings.Contains(resp.Error.Description, "message") {
+			return nil, ErrMsgNotFound
+		}
+		return nil, fmt.Errorf("nats: %s", resp.Error.Description)
 	}
 
 	msg := resp.Message
@@ -861,6 +864,7 @@ func (js *js) DeleteMsg(name string, seq uint64, opts ...JSOpt) error {
 	return nil
 }
 
+// purgeRequest is optional request information to the purge API.
 type streamPurgeRequest struct {
 	// Purge up to but not including sequence.
 	Sequence uint64 `json:"seq,omitempty"`
diff --git a/kv.go b/kv.go
index d12e50024..3f399c2b0 100644
--- a/kv.go
+++ b/kv.go
@@ -17,6 +17,7 @@ import (
 	"context"
 	"errors"
 	"fmt"
+	"regexp"
 	"strconv"
 	"strings"
 	"time"
@@ -40,14 +41,16 @@ type KeyValue interface {
 	Create(key string, value []byte) (revision uint64, err error)
 	// Update will update the value iff the latest revision matches.
 	Update(key string, value []byte, last uint64) (revision uint64, err error)
-	// Delete the key and all revisions.
+	// Delete will place a delete marker and leave all revisions.
 	Delete(key string) error
+	// Purge will remove the key and all revisions.
+	Purge(key string) error
 	// WatchAll will invoke the callback for all updates.
 	WatchAll(cb KeyValueUpdate) (*Subscription, error)
 	// Watch will invoke the callback for any keys that match keyPattern when they update.
 	Watch(keys string, cb KeyValueUpdate) (*Subscription, error)
-	// List will return all values for the key.
-	List(key string) ([]KeyValueEntry, error)
+	// History will return all histroical values for the key.
+	History(key string) ([]KeyValueEntry, error)
 	// Bucket returns the current bucket name.
 	Bucket() string
 }
@@ -66,9 +69,10 @@ type KeyValueConfig struct {
 
 // Used to watch all keys.
 const (
-	AllKeys = ">"
-	kvop    = "KV-Operation"
-	kvdel   = "DEL"
+	KeyValueMaxHistory = 64
+	AllKeys            = ">"
+	kvop               = "KV-Operation"
+	kvdel              = "DEL"
 )
 
 type KeyValueOp uint8
@@ -78,7 +82,7 @@ const (
 	KeyValueDelete
 )
 
-// Retrieved entry for Get or List or Watch.
+// KeyValueEntry is a retrieved entry for Get or List or Watch.
 type KeyValueEntry interface {
 	// Bucket is the bucket the data was loaded from.
 	Bucket() string
@@ -96,15 +100,19 @@ type KeyValueEntry interface {
 	Operation() KeyValueOp
 }
 
-// Callback handler for KeyValue updates.
+// KeyValueUpdate is the callback handler for KeyValueEntry updates.
 type KeyValueUpdate func(v KeyValueEntry)
 
 // Errors
 var (
-	ErrBucketNameRequired = errors.New("nats: bucket name is required")
-	ErrInvalidBucketName  = errors.New("nats: invalid bucket name")
-	ErrBucketNotFound     = errors.New("nats: bucket not found")
-	ErrBadBucket          = errors.New("nats: bucket not valid key-value store")
+	ErrKeyValueConfigRequired = errors.New("nats: config required")
+	ErrInvalidBucketName      = errors.New("nats: invalid bucket name")
+	ErrInvalidKey             = errors.New("nats: invalid key")
+	ErrBucketNotFound         = errors.New("nats: bucket not found")
+	ErrBadBucket              = errors.New("nats: bucket not valid key-value store")
+	ErrKeyNotFound            = errors.New("nats: key not found")
+	ErrKeyDeleted             = errors.New("nats: key was deleted")
+	ErrHistoryToLarge         = errors.New("nats: history limited to a max of 64")
 )
 
 const (
@@ -114,12 +122,15 @@ const (
 	kvNoPending       = "0"
 )
 
+// Regex for valid keys and buckets.
+var (
+	validBucketRe = regexp.MustCompile(`\A[a-zA-Z0-9_-]+\z`)
+	validKeyRe    = regexp.MustCompile(`\A[-/_=\.a-zA-Z0-9]+\z`)
+)
+
 // KeyValue will lookup and bind to an existing KeyValue store.
 func (js *js) KeyValue(bucket string) (KeyValue, error) {
-	if bucket == _EMPTY_ {
-		return nil, ErrBucketNameRequired
-	}
-	if strings.Contains(bucket, ".") {
+	if !validBucketRe.MatchString(bucket) {
 		return nil, ErrInvalidBucketName
 	}
 	stream := fmt.Sprintf(kvBucketNameTmpl, bucket)
@@ -147,9 +158,13 @@ func (js *js) KeyValue(bucket string) (KeyValue, error) {
 
 // CreateKeyValue will create a KeyValue store with the following configuration.
 func (js *js) CreateKeyValue(cfg *KeyValueConfig) (KeyValue, error) {
-	if cfg == nil || cfg.Bucket == _EMPTY_ {
-		return nil, ErrBucketNameRequired
+	if cfg == nil {
+		return nil, ErrKeyValueConfigRequired
 	}
+	if !validBucketRe.MatchString(cfg.Bucket) {
+		return nil, ErrInvalidBucketName
+	}
+
 	if strings.Contains(cfg.Bucket, ".") {
 		return nil, ErrInvalidBucketName
 	}
@@ -157,11 +172,15 @@ func (js *js) CreateKeyValue(cfg *KeyValueConfig) (KeyValue, error) {
 		return nil, err
 	}
 
-	// Default to 1 for history.
+	// Default to 1 for history. Max is 64 for now.
 	history := int64(1)
 	if cfg.History > 0 {
+		if cfg.History > KeyValueMaxHistory {
+			return nil, ErrHistoryToLarge
+		}
 		history = int64(cfg.History)
 	}
+
 	replicas := cfg.Replicas
 	if replicas == 0 {
 		replicas = 1
@@ -194,6 +213,9 @@ func (js *js) CreateKeyValue(cfg *KeyValueConfig) (KeyValue, error) {
 
 // DeleteKeyValue will delete this KeyValue store (JetStream stream).
 func (js *js) DeleteKeyValue(bucket string) error {
+	if !validBucketRe.MatchString(bucket) {
+		return ErrInvalidBucketName
+	}
 	stream := fmt.Sprintf(kvBucketNameTmpl, bucket)
 	return js.DeleteStream(stream)
 }
@@ -224,14 +246,28 @@ func (e *kve) Created() time.Time    { return e.created }
 func (e *kve) Delta() uint64         { return e.delta }
 func (e *kve) Operation() KeyValueOp { return e.op }
 
+func keyValid(key string) bool {
+	if len(key) == 0 || key[0] == '.' || key[len(key)-1] == '.' {
+		return false
+	}
+	return validKeyRe.MatchString(key)
+}
+
 // Get returns the latest value for the key.
 func (kv *kvs) Get(key string) (KeyValueEntry, error) {
+	if !keyValid(key) {
+		return nil, ErrInvalidKey
+	}
+
 	var b strings.Builder
 	b.WriteString(kv.pre)
 	b.WriteString(key)
 
 	m, err := kv.js.GetLastMsg(kv.stream, b.String())
 	if err != nil {
+		if err == ErrMsgNotFound {
+			err = ErrKeyNotFound
+		}
 		return nil, err
 	}
 
@@ -246,7 +282,7 @@ func (kv *kvs) Get(key string) (KeyValueEntry, error) {
 	// Double check here that this is not a DEL Operation marker.
 	if len(m.Header) > 0 && m.Header.Get(kvop) == kvdel {
 		entry.op = KeyValueDelete
-		return entry, ErrMSgNotFound
+		return entry, ErrKeyDeleted
 	}
 
 	return entry, nil
@@ -254,6 +290,10 @@ func (kv *kvs) Get(key string) (KeyValueEntry, error) {
 
 // Put will place the new value for the key into the store.
 func (kv *kvs) Put(key string, value []byte) (revision uint64, err error) {
+	if !keyValid(key) {
+		return 0, ErrInvalidKey
+	}
+
 	var b strings.Builder
 	b.WriteString(kv.pre)
 	b.WriteString(key)
@@ -273,7 +313,7 @@ func (kv *kvs) Create(key string, value []byte) (revision uint64, err error) {
 	}
 	// TODO(dlc) - Since we have tombstones for DEL ops for watchers, this could be from that
 	// so we need to double check.
-	if e, err := kv.Get(key); err == ErrMSgNotFound {
+	if e, err := kv.Get(key); err == ErrKeyDeleted {
 		return kv.Update(key, value, e.Revision())
 	}
 	return 0, err
@@ -281,6 +321,10 @@ func (kv *kvs) Create(key string, value []byte) (revision uint64, err error) {
 
 // Update will update the value iff the latest revision matches.
 func (kv *kvs) Update(key string, value []byte, revision uint64) (uint64, error) {
+	if !keyValid(key) {
+		return 0, ErrInvalidKey
+	}
+
 	var b strings.Builder
 	b.WriteString(kv.pre)
 	b.WriteString(key)
@@ -295,35 +339,42 @@ func (kv *kvs) Update(key string, value []byte, revision uint64) (uint64, error)
 	return pa.Sequence, err
 }
 
-// Delete the key and all revisions.
+// Delete will place a delete marker and leave all revisions.
 func (kv *kvs) Delete(key string) error {
+	return kv.delete(key, false)
+}
+
+// Purge will remove the key and all revisions.
+func (kv *kvs) Purge(key string) error {
+	return kv.delete(key, true)
+}
+
+func (kv *kvs) delete(key string, purge bool) error {
+	if !keyValid(key) {
+		return ErrInvalidKey
+	}
+
 	var b strings.Builder
 	b.WriteString(kv.pre)
 	b.WriteString(key)
 
 	// DEL op marker. For watch functionality.
-	m := Msg{Subject: b.String(), Header: Header{}}
+	m := NewMsg(b.String())
 	m.Header.Set(kvop, kvdel)
-	paf, err := kv.js.PublishMsgAsync(&m)
-	if err != nil {
-		return err
-	}
-	err = kv.js.purgeStream(kv.stream, &streamPurgeRequest{Subject: b.String(), Keep: 1})
-	if err != nil {
-		return err
+	_, err := kv.js.PublishMsg(m)
+	if err == nil && purge {
+		err = kv.js.purgeStream(kv.stream, &streamPurgeRequest{Subject: b.String()})
 	}
+	return err
+}
 
-	// Double check the pubAck future.
-	select {
-	case <-paf.Ok():
-		return nil
-	case err := <-paf.Err():
-		return err
+// History will return all values for the key.
+func (kv *kvs) History(key string) ([]KeyValueEntry, error) {
+	// Do quick check to make sure this is a legit key with history.
+	if _, err := kv.Get(key); err != nil && err != ErrKeyDeleted {
+		return nil, err
 	}
-}
 
-// List will return all values for the key.
-func (kv *kvs) List(key string) ([]KeyValueEntry, error) {
 	o, cancel, err := getJSContextOpts(kv.js.opts)
 	if err != nil {
 		return nil, err
@@ -396,6 +447,7 @@ func (kv *kvs) WatchAll(cb KeyValueUpdate) (*Subscription, error) {
 // Watch will fire the callback when a key that matches the keys pattern is updated.
 // keys needs to be a valid NATS subject.
 func (kv *kvs) Watch(keys string, cb KeyValueUpdate) (*Subscription, error) {
+	// Could be a pattern so don't check for validity as we normally do.
 	var b strings.Builder
 	b.WriteString(kv.pre)
 	b.WriteString(keys)
diff --git a/nats.go b/nats.go
index 49a76e8c6..777d540b8 100644
--- a/nats.go
+++ b/nats.go
@@ -155,7 +155,7 @@ var (
 	ErrPullSubscribeToPushConsumer  = errors.New("nats: cannot pull subscribe to push based consumer")
 	ErrPullSubscribeRequired        = errors.New("nats: must use pull subscribe to bind to pull based consumer")
 	ErrConsumerNotActive            = errors.New("nats: consumer not active")
-	ErrMSgNotFound                  = errors.New("nats: message not found")
+	ErrMsgNotFound                  = errors.New("nats: message not found")
 )
 
 func init() {
diff --git a/test/js_test.go b/test/js_test.go
index 1c96656b9..e31042046 100644
--- a/test/js_test.go
+++ b/test/js_test.go
@@ -1597,7 +1597,7 @@ func testJetStreamManagement_GetMsg(t *testing.T, srvs ...*jsServer) {
 
 		// Try to fetch the same message which should be gone.
 		_, err = js.GetMsg("foo", originalSeq)
-		if err == nil || err.Error() != `no message found` {
+		if err == nil || err != nats.ErrMsgNotFound {
 			t.Errorf("Expected no message found error, got: %v", err)
 		}
 	})
diff --git a/test/kv_test.go b/test/kv_test.go
index 8a47e9efe..f5bdc9384 100644
--- a/test/kv_test.go
+++ b/test/kv_test.go
@@ -58,7 +58,7 @@ func TestKeyValueBasics(t *testing.T) {
 	err = kv.Delete("name")
 	expectOk(t, err)
 	_, err = kv.Get("name")
-	expectErr(t, err)
+	expectErr(t, err, nats.ErrKeyDeleted)
 	r, err = kv.Create("name", []byte("derek"))
 	expectOk(t, err)
 	if r != 3 {
@@ -78,7 +78,7 @@ func TestKeyValueBasics(t *testing.T) {
 	expectOk(t, err)
 }
 
-func TestKeyValueList(t *testing.T) {
+func TestKeyValueHistory(t *testing.T) {
 	s := RunBasicJetStreamServer()
 	defer shutdown(s)
 
@@ -94,7 +94,7 @@ func TestKeyValueList(t *testing.T) {
 		expectOk(t, err)
 	}
 
-	vl, err := kv.List("age")
+	vl, err := kv.History("age")
 	expectOk(t, err)
 
 	if len(vl) != 10 {
@@ -237,6 +237,41 @@ func TestKeyValueDeleteStore(t *testing.T) {
 	expectErr(t, err)
 }
 
+func TestKeyValueDeleteVsPurge(t *testing.T) {
+	s := RunBasicJetStreamServer()
+	defer shutdown(s)
+
+	nc, js := jsClient(t, s)
+	defer nc.Close()
+
+	kv, err := js.CreateKeyValue(&nats.KeyValueConfig{Bucket: "KVS", History: 10})
+	expectOk(t, err)
+
+	put := func(key, value string) {
+		_, err := kv.Put(key, []byte(value))
+		expectOk(t, err)
+	}
+
+	// Put in a few names and ages.
+	put("name", "derek")
+	put("age", "22")
+	put("name", "ivan")
+	put("age", "33")
+	put("name", "rip")
+	put("age", "44")
+
+	kv.Delete("age")
+	entries, err := kv.History("age")
+	expectOk(t, err)
+	// Expect three entries and delete marker.
+	if len(entries) != 4 {
+		t.Fatalf("Expected 4 entries for age after delete, got %d", len(entries))
+	}
+	kv.Purge("name")
+	_, err = kv.History("name")
+	expectErr(t, err, nats.ErrKeyNotFound)
+}
+
 // Helpers
 
 func client(t *testing.T, s *server.Server) *nats.Conn {
diff --git a/test/object_test.go b/test/object_test.go
index 842add2f3..a7613cd93 100644
--- a/test/object_test.go
+++ b/test/object_test.go
@@ -377,9 +377,6 @@ func TestObjectWatch(t *testing.T) {
 	err = obs.Delete("A")
 	expectOk(t, err)
 
-	// FIXME(dlc) - I think there is a bug in server on rollup that causes an update on "B" here.
-	expectUpdate("B")
-
 	expectUpdate("A")
 	expectNoMoreUpdates()