How do I reduce my lag when playing CS on wireless?

I can't really play CS anymore because my lag is horrible. I have a wireless connection, and it lags horribly. Is there any way to fix this?

 

How have you determined the lag was caused by wireless. If your using wireless b you could upgrade to wireless g.

 

Lag on a wireless system can be caused by a barrage of things including to other wireless objects, OS updates, filmware/driver updates, piping between walls/hot water pipes/heater pipes, distance to wireless station, number of walls to station, a basement location, settings on the wireless router, windows SP2 firewall/software firewall/hardware firewall, people from outside using your connection, malware, and portblocking to name a few .

I am currently on a 125mbps wireless system throughout my house and i get absolutly no lag on any game I play or anything eles I do.

 

How would it not help it would give him a faster connection to the modem which even though his connection is still probably faster then the internet connection anyway, It would still improve times between the router and his computer.