In my last article, I described the basics of improv.  Improv is the art of doing theater scene work without a script.  The improv most people are familiar with is improv comedy and the TV show Whose Line Is It Anyway?  
Doing improv can change your life for the better if you let it.  I've found its made me a better person.  Here are some of the ways it might change your life.  
Improv isn't the best or funniest art form, but it might be the bravest.  Getting up on stage in front of a room full of strangers without a plan can be terrifying.  Not knowing what your scene partners will say can be terrifying.  Telling a joke and having it bomb is gut wrenching.  Not letting your team mates down is an incredible amount of pressure.  Getting on stage and going blank is a not uncommon response in first time improvisers.  
You will have to face your fears if you do improv.  Fear of failure, social anxiety, and fear of making an ass of yourself all need to be dealt with.  If you can deal with these things, you will be able to perform far better under pressure than most people.  The best improvisers can relax under pressure.  
The first rule of improv is "yes, and".  This means that you must listen to you partner and accept the other person's reality, even if you can't see it.  You don't argue, belittle, or negate what they have to say.  "Yes, and" guarantees that you are open to the other person and you are influenced by them.  This is a very basic first step in all sorts of relationships, from marriage to business.  Practicing "yes, and" at improv will make you more aware of how accepting you are in real life.
Saying "no" is important as well, but it is more effective to say "no" after you have really listened to and accepted what the other person has to say.  
Improv will make you more creative.  We all have a wildly intuitive and creative side to us.  We can all pick up an object, like a traffic cone, and imagine using it in a million different ways and a million different situations.  Real life can beat this sort of intuition out of us.  Doing improv allows you to start seeing the possibilities in life again.  
Being on stage and having to think on your feet means that you have to listen to your inner voice.  What are you telling yourself, in the moment?  Do you really listen to your creative voice, or do you shut it down most of the time?  Doing improv will get you back in touch with that voice, your creative wellspring.  
Improv can change you life, if you let it.