If your coworkers are making your working environment hostile through unwelcome conduct or statements, that might be sexual harassment. The best place to start in this type of situation is with the perpetrators: Tell your coworkers, clearly and firmly, that their behavior offends you and has to stop. This often works. If it doesn't, use your employer's procedure for making internal complaints of harassment. In the absence of a policy, ask your manager or someone in the human resources department how to make a sexual harassment complaint. This gives your company a chance to stop the behavior; it's also a necessary prerequisite if you might later take legal action. For more information, see Nolo's article Fighting Sexual Harassment.