I have used Baby sign language with my DD, she doesn't have special needs, we just use it as an added communication tool and as a way to lessen the frustration associated with communication challenges when vocab doesn't match desires

If you are interested in my story, we started at about 12 months and she used her first sign at 15 months. From there she picked up signs really quickly. I started consulting a baby sign book but found it a bit frustrating. I then went to the Auslan webpage and looked up signs that were appropriate for us on their sign bank. (Highly recommended as they show little video snippets of each sign which is much easier to follow than a still picture, you can google Auslan to find it.)

My mother is a Kindergarten teacher and she uses Makaton a lot. If she has a special needs child in her group she will teach all the children in the class some basic Makaton so that they are all able to communicate together. Mum gave me a Makaton book as a reference and I have used a mix of both Makaton and Auslan signs for DD since. I tend to use the ones that work best for us.

The book I have is "The Makaton Vocabulary - Australian (Auslan) Edition by Aileen Ryan, Ella Keesing and Judith Cowley. (ISBN 0-646-41712-6. It has excellent line drawings of each of the signs in it. The book is pubilshed by Makaton Australia with an office in Victoria: Level 1 /830 Whitehorse Road Box Hill (03 9899 8684).

Makaton is specifically designed to encourage language development in children and adults with communication difficulties and as far as I know there are no problems at all beginning at 3 or even later. I think that children who have difficulty communicating (whatever their age or communication challenges) really really love the fact that they are able to get their message across. My DD gets so excited when people understand her hand signals and there is an added bonus in that people are really keen to get involved in the signing and trying to work out what she wants. It is really a lovely interaction. With regards to verbal communication, there is heaps of evidence that suggests that non-verbal signing encourages the use of verbal communication and I am certainly seeing that with my DD (18 months now).

A great example of how much I love the signing was when I over heard from the other end of the house, my DD saying to my DH something that sounded like "ba-ee". It was something I did not recognise as a word she uses and I was wondering what she seemed to want and how on earth my DH would work it out. Very quickly I heard my DH say, "oh bubbly, you want bubbly water!" She had used the Auslan sign for Bubbles that we taught her the day before and was asking for soda water! It was really lovely to know that we could understand what she wanted and lessen her frustration.

I hope this helps a little, as you can see I am really enjoying the Makaton/baby sign experience. If you have any other questions, please don't hesitate to ask!