A few well-chosen references can set you apart from other applicants and prove to employers that you’re a competent, professional and hardworking candidate. If your boss can’t know you plan to leave, however, you’ll have to be selective in who you ask. Only offer references from people you can trust to stay mum about your job search and who will talk you up to potential employers.

Enlist Trusted Colleagues

If you have a good relationship with your co-workers, ask one of them to provide a reference. Prospective employers will have more confidence in your abilities if they can speak to someone who can vouch for your current knowledge, skill set and work ethic instead of someone who worked with you several years ago or who does not know you in a professional capacity. Before asking a colleague to be a reference, ensure she supports your job search and understands the importance of using discretion. Ask her not to let it slip to other co-workers, no matter how much she trusts them to keep the subject under wraps.

Ask Former Bosses

Some employers have more faith in references from supervisors than those that come from colleagues. They want someone who can speak to them “boss-to-boss" and offer insight into what you’re like as a subordinate. If you left previous jobs on good terms, you can ask bosses from those companies to testify to your qualifications. Stick to managers you’ve worked for in the last five years. If your only references are people who knew you 10 or 15 years ago, employers may wonder why no one from your most recent jobs can put in a good word for you. If you’re a recent college graduate, ask former internship supervisors to speak to employers on your behalf.

Search Your Network

You likely know people outside of your workplace who can offer positive, thorough recommendations to employers. Consider asking people you volunteer with or serve on committees for community or professional associations. If you have a mentor, offer her name especially if she’s well-known within the industry. Only ask people who can describe your skills in a professional setting, however, and don’t ask close friends or relatives. No matter how credible and objective they are, employers likely won’t take their opinions seriously.

Draw on Academic Connections

If you graduated within the last one to two years, ask former professors to provide a reference for you. They can address many of the same issues as supervisors can, in addition to offering the authoritative reference that puts prospective employers’ minds at ease. For example, your professors can confirm you have excellent organizational skills by noting that you consistently turned in assignments on time or early. They can also discuss your people and teamwork skills by mentioning that you always pulled your weight when working on group projects.