Which dialect of LISP should I use?

It really depends on what your requirements are:


Assuming you want:
1) The most documentation
2) Supported on a large number of platforms
3) Supported by the most number of IDEs
4) Strong commercial support for your enterprise from a number of vendors
Then you're looking at Common Lisp


If you're looking for a dialect that is
1) Really fun to learn
2) Has some classic Computer Science texts written for it
Then you're looking at Scheme


If you're looking for a dialect that
1) Has support for a large number of platforms
2) Is integrated into modern libraries like the JDK and the CLR
3) Has a really dynamic passionate community
4) Is still evolving and is the hottest thing on the block
5) Has a growing number of books published for it
Then you're looking at Clojure


More discussion

• Stack overflow discussion on Lisp Dialects
• Metafilter discussion on Lisp Dialects