What kind of environment are you talking about? Streetfighting, kickboxing, mma? If you're a good infighter that almost nullifies your opponents ability to kick. Also the cross is the archrival of the roundhouse kick; look at you opponent's hip rotation which precedes the kick. As soon as you see it throw the cross with bad intentions. Your opponent won't be able to evade it because he'll be standing on one foot when it lands. That being said when fighting a good kicker you must bring the fight to him. Good kickers try to create space to set up their kicks (a la "Crocop") and unless you are a fantastic counterpuncher playing the counterpunching or outfighting game is a risky business.
Velo gives good advice. If the guy is a good kicker, take it inside. If the guy has good hands and legs, take it to the ground. Watch the guys with a long reach. You get too wrapped up in hanging back to avoid thier freakishly long arms and set yourself up for a boot in the head. Push the fight though. You have to have a good base to kick from if you want you kick to count. If you press forward and keep him on his heels he'll have less opertunities to kick. Last but definetly not least, learn how to avoid (dodge), check and how to absorb, if needs be, as much of the kick as possible. Watch Tito Ortiz take a foot to the noodle. He's got his arm up sung to the head and he moves with the impact. He doesn't just stand there like a statue.