Different organizations have varying policies regarding romance in the workplace. Before asking your co-worker out to lunch, thoroughly review your company's policy on dating and sexual harassment at the office. Potential issues may arise if you are your co-worker's supervisor or have influence over her pay, performance reviews or promotions.

Before taking the plunge and asking your co-worker to lunch, try striking up conversations at meetings, in the break room or anywhere the opportunity presents itself. Take notice of potential cues that she may be interested or uninterested in your advances. Signs of attraction include laughing, smiling, making eye contact, playing with her hair and leaning in toward you during the conversation. If you notice that your co-worker breaks away from conversation with you, is closed off, does not make eye contact or otherwise distances herself from you, chances are she is not interested and may not welcome your invitation to a lunch date.

Discussing expense reports and committee meetings may not be your idea of a great first date, but using work as an icebreaker might get your co-worker to agree to a lunch date. If your work-related lunch date is going well and your co-worker displays signs that she might be interested in you, tell her how much you enjoyed the outing and ask if she'd like to go to lunch outside of work.

The line between asking your co-worker out and sexual harassment can be thin, and your behavior could fall into an ethically grey area. Although the safest course is to not act on your desires at all, if you must make a move, avoid doing anything that might make your co-worker feel uncomfortable. This includes repeatedly asking her to lunch, invading her personal space, making suggestive remarks or making professionally inappropriate jokes. If your co-worker indicates that she is not interested in a date, thank her for her time and head back to your desk.