We have been developing a senes of Sesign (speech design tools), TTS systems with the special function of manipulating prosodic parameters via a GUI (Graphical User Interface). All are intended to help the user create speech messages in a trial-and-error manner. This paper reports the following three advances in Sesign. (1) To extend the scope of Sesign, we added an American English TTS system. (2) A markup labguage approach called MSCL (Multi-layered Speech Control Language) is used together with the GUI-based approach. (3) We performed field trials using speech messages created by Sesign. One of the most successful examples is the MyPartner service, which informs the user of up-to-date information; the sentences generated by Sesign are used in combination with TTS output.