Dating a co-worker isn't the taboo it once was. In fact, 84 percent of millennials (those born after 1981) say they have no problem with dating a co-worker, according to the "New York Magazine" article "Why a Woman Should Never Date Her Co-Workers." However, for a variety of reasons, you may choose not to date someone you spend so many waking hours with. Thankfully, there are ways to let your co-worker down easily and maintain your professional relationship.

Step 1

Tell your co-worker you're simply not interested, and treat him like any other suitor. This direct, honest method gets your point across and won't lead to any confusion. Use "I" statements so your co-worker won't take you saying no personally. For instance, you might say something like, "I really love working together, but I just don't feel a connection that way" or "I really enjoy our conversations and friendship, but I'm looking for something different at this point, and I want to be upfront about our chances."

Step 2

Deflect your co-worker's question if the direct approach isn't really your style. One way of doing this is when he asks for your number, ask for his information instead. By doing this, you're putting yourself in a position to call the shots. Then, you can simply decide not to call. Another deflection strategy is to say that, sure, you'd love to hang out -- but as part of a group, not as a couple. You might say, "I'd love to do something! Let's check and see what the whole team is up to on Friday" or "Sounds great -- I'll ask so-and-so if she wants to come, too."

Step 3

Point out the potential awkwardness if things go badly if he still doesn't seem to get the message. Explain that you really don't want to have to attend trainings, lunches and meetings with an ex. Politely say to him that the potential stress dating might cause simply isn't worth it to you. Say something like, "I would just feel so awful if things didn't work out between us. I really want to keep work a neutral environment -- hope you can understand that."

Step 4

State that dating him could damage your professional reputation -- which should end the conversation once and for all. Many companies have policies prohibiting co-workers from dating. If this is true for you, then you have the perfect out. Tell your co-worker how important your career is to you and that you really don't want to tie your reputation to anyone else's or have your boss think less of you.