It depends on what you are trying to do.

Personally I've tried out symfony, cakephp and codeigniter.

Symfony was yuck.

Cakephp was very good for prototyping but quite strict after a while and
difficult to really get under the covers and use properly.

Codeigniter was the most flexible and easiest to get to grips with, plus it has a very good documentation system, and some nice tutorial videos around.

Try codeigniter first and if it doesn't meet your needs then look at cakephp.

Kind regards, Spencer

I'm not using one myself at the moment but, cakephp and codeigniter do seem to be the favourites and, anything with cake in it must be good!

I don't know if you really consider Smarty a framework or not, but I've been using it for 7 years (since PHPLib went bust) to develop apps that separate code and layout, and the cache functions are just awesome. Wish I could say I had more experience in this area. Smarty has sure sped up development for me and it is still in active development. I'm going to take a look at codeigniter now that it has been mentioned too.

Another vote for Code Igniter here. I've also tried a bunch of frameworks like CakePHP, Symfony, Mojavi, Zend... While CodeIgniter wasn't exactly the best, I find it very easy to use and I can make sites "rapidly"... Many still claims Symfony to be the most powerful one once you get the hang of it *cough* symfony configs and setup *cough*...

If I were to use another framework besides Code Igniter, I would definitely consider Zend's very own as it was built and implemented "naturally" from base PHP coding style. The only reason I still use Code Igniter is because of how fast I can make apps from it.

A vote for CakePHP here. I use it for everything!

There is a fairly steep learning curve with it however but once you're through that its so simple.

Codeigniter is great as well.

I'll also mirror Marks suggestion. Zend is a beast and capable of a hell of a lot of features out of the box.

Either of those 3 have my tick of approval

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