2011 was the second year we have used Mosquito Squad. As stated in my 2010 review, we had a serious mosquito problem. Being a gardener and generally an outdoorsy person, I was going through at least one can of OFF insect repellent every week (that's just for me - not counting my husband, our kids and grandkids and any other unfortunates who visited). I figured that, altogether, we were spending about 30.00 per month on insect repellents. I had also tried insect repellent clothing, herbal-based repellents, citronella, incense, and literally every other product out there except the very expensive carbon dioxide-based traps. Having Mosquito Squad come out and spray was by far the best solution. Each treatment lasted about 21 days, and if it didn't (once or twice the whole year), I just sent an email (I could have called, but I prefer email) and they re-sprayed immediately at no charge (once, they were back within an hour of the time I sent the email). Being a person who worries about chemicals (including DEET), I emailed John early on to ask what chemicals are used in the mosquito spray. He replied (immediately) that it is permethrin, which is derived from a type of chrysanthemum. I had previously researched permethrin and had decided it was the most effective chemical that was acceptable to me. In case you're wondering, I have not noticed any decrease in beneficial insects - such as pollinating bees - in my garden. The bottom line is I would very highly recommend Mosquito Squad of Raleigh-Cary to anyone with a mosquito problem.