diff --git a/api/api.go b/api/api.go
index 953d80f..489c629 100644
--- a/api/api.go
+++ b/api/api.go
@@ -13,6 +13,8 @@ type Keybase struct {
 type keybase interface {
 	ChatSendText(user string, message ...string) (chatOutResultResult, error)
 	ChatSendTextTeam(team, channel, message string) (chatOutResultResult, error)
+	ChatSendReaction(user, reaction string, messageId int) (chatOutResultResult, error)
+	ChatSendReactionTeam(team, channel, reaction string, messageId int) (chatOutResultResult, error)
 	ChatList() ([]chatOutResultConversations, error)
 	LoggedIn() bool
 	Username() string
diff --git a/api/chatOut.go b/api/chatOut.go
index 12c4d50..9b1efe7 100644
--- a/api/chatOut.go
+++ b/api/chatOut.go
@@ -20,8 +20,9 @@ type chatOutMessage struct {
 	Body string `json:"body"`
 }
 type chatOutOptions struct {
-	Channel chatOutChannel `json:"channel"`
-	Message chatOutMessage `json:"message"`
+	Channel   chatOutChannel `json:"channel"`
+	MessageID int            `json:"message_id"`
+	Message   chatOutMessage `json:"message"`
 }
 type chatOutParams struct {
 	Options chatOutOptions `json:"options"`
@@ -110,6 +111,38 @@ func (k Keybase) ChatSendTextTeam(team, channel string, message ...string) (chat
 	return r.Result, nil
 }
 
+// ChatSendReaction() sends a reaction to a user's message.
+func (k Keybase) ChatSendReaction(user, reaction string, messageId int) (chatOutResultResult, error) {
+	m := chatOut{}
+	m.Method = "reaction"
+	m.Params.Options.Channel.Name = user
+	m.Params.Options.MessageID = messageId
+	m.Params.Options.Message.Body = reaction
+
+	r, err := chatAPIOut(k.path, m)
+	if err != nil {
+		return chatOutResultResult{}, err
+	}
+	return r.Result, nil
+}
+
+// ChatSendReactionTeam() sends a reaction to a message on a team.
+func (k Keybase) ChatSendReactionTeam(team, channel, reaction string, messageId int) (chatOutResultResult, error) {
+	m := chatOut{}
+	m.Method = "reaction"
+	m.Params.Options.Channel.Name = team
+	m.Params.Options.Channel.MembersType = "team"
+	m.Params.Options.Channel.TopicName = channel
+	m.Params.Options.MessageID = messageId
+	m.Params.Options.Message.Body = reaction
+
+	r, err := chatAPIOut(k.path, m)
+	if err != nil {
+		return chatOutResultResult{}, err
+	}
+	return r.Result, nil
+}
+
 // ChatList() returns a list of all conversations.
 func (k Keybase) ChatList() ([]chatOutResultConversations, error) {
 	m := chatOut{}