Mold and mildew

How do you effectively get rid of mold and mildew? This season is very rainy and being allergic to mold makes it very hard. I hear mold spores can last for up to 15 years. Is that true and if so how do you completely get rid of the mold and mildew?

Sometimes you have to resort to ripping walls out of your home. I've heard this having to be done many times. Sometimes even that doesn't resolve it as it can be in the wood.