How do I become a pool lifeguard?

I've been searching on the internet for certain information, but I can't find it. I know I need a National Pool Lifeguard Qualification (or something like that), but I would also like to know: are there any other prerequisites (eg. swim 200 metres in 3 different strokes, previous first aid training, etc)? Anything else you think is important to know?
Thanx!

This website will give you all the info you need to know

you need to be able to do basic first aid and life support CPR etc
swim test such as a timed swim which isn't too difficult tow someone through the water and dive to the bottom of the pool

http://www.lifesavers.org.uk/iql/index.h...

If you are in the US then chances are you will need to be Red Cross certified in Lifeguarding. Red Cross Lifeguarding also certifies you in CPR, AED, and teaches you basic First Aid. The prerequisite for the class is you must be 15 years old, be able to swim 100 meters front crawl, 100 meters breast stroke, and another 100 meters of either front crawl or breast stroke. Then you will have 1:20 to swim 20 yards, retrieve a 10 pound brick from a depth of 7 ft. or more, return to the side with the brick out of the water, and exit the pool.
It sounds pretty hard but it really isn't. 100 meters=4 lengths of a pool and a 10 pound brick in the water is not heavy. I have been a lifeguard for 6 years and now that I am at the end of my college career my experience is leading to several job offers or advancements with my employer because I am already certified so they don't have to pay for it or wait for e to get it.
Good Luck!