Where do you look next for the people that will be the face of your business? How do you improve your odds of finding, engaging, and hiring great employees?

Once you’ve exhausted your list of known candidates, it’s time to look to your internal sources. These are the people who have worked with you, for you, or in your industry. Maybe you couldn’t pick them out of a line-up, but you have a handle on them. Brainstorm with your top talent and start taking names.

Internal sources include:

Great employees who left on good terms. Don’t forget temporary workers and interns. Not only do they know what you’re about, they have likely gained a wealth of experience since you last met, and might be the perfect addition to your staff. These potential employees will have a much shorter learning curve than new hires and will hit the ground running, saving you a great deal of time and money when it comes to training.

“Hey-remember Glen? That great intern we had last year? He would knock this project out of the park. Let’s track him down!”

Your retirees. Retired people of all ages are returning to the workforce like never before. Retirees often miss the financial and social benefits of the workplace. Consider retirees from other companies and industries as well.

Seniors come from an era where employees had a solid work ethic. These employees will have a lifetime of knowledge and their experience will balance your young, green and eager team members. Older employees provide an entirely different point of view, with the added benefit of insight into their demographic. In many cases they have a lot more freedom (and a lot fewer responsibilities) than their junior counterparts. They are rarely juggling toddlers, another part-time job, or a demanding university professor. Seniors tend to be extremely reliable and they are an overlooked sector of job seekers.

Applicants you interviewed in the past. They’ve already expressed an interest in working with your company and they’ve been assessed and vetted. Most of your work here is already done.

Applicants you almost hired. They were second choice last time. They’ve had time to grow, learn, and mature. Give them a second look.

Applicants you attempted to hire. They may have dropped out of the interview or application process or declined a past offer. Things change. Perhaps they are ready now. There’s only one way to find out.

Applicants who needed more experience. They’ve acquired more life and work experience and might now be a perfect fit for your team. Ask them.

The ‘Just Looking’ Crowd. This group of candidates includes the elusive top-tier talent currently working for your competition, and although they are the most difficult to attract, they are a primary target. These are the people that are already making headlines in the industry and have their choice of employers.

Approach them as you would a prospective customer. Identify them, target them, then sell them on your company and the position. A social media platform that doesn’t require individuals to formally apply for a position with your company can serve as an introduction, and eventually turn passive applicants to active ones. Whether it is through your website, or a social media profile, allowing interested parties a chance to get to know your company with no strings attached is a proven way to secure future talent-especially individuals that don’t even know they’re looking yet.

Now, let’s look at some external sources.

You are going to have to physically go out and find these unknown candidates, so this is a perfect time to involve your HR team and top-shelf talent.

Universities. Over 80% of American companies recruit on campus. How can you find great talent when the prestigious schools have been picked over by the big companies?

Large firms often overlook smaller, more remote schools in favor of the Ivy League, top universities and tech schools, and even their own alma maters. They are inundated with applicants and rarely need to look any further for top-tier talent, leaving first-rate grads from smaller university and college campuses out in the cold. Bring them in.

High schools. Be on their radar as early as possible. Be memorable. Send captivating speakers to their job fairs. People don’t forget who took an interest in them early on. Pay particular attention to students who have won scholarships and academic awards, and enlist the help of teachers to recruit students showing interest and aptitude in your field.

Your community. Throw your company’s hat in the ring for local employer excellence awards. Sponsor relevant teams and events. Do an interview with the local paper. Stand out, and be known for being a community-driven business.

In 2003, Canada’s Purolator employees decided to take action in their community by creating Purolator Tackle Hunger, an initiative that has delivered more than 18 million meals to families across the country. This kind of good will can raise your profile in the community.

Forums and boards. Look for smart, relevant conversations among people using industry-specific platforms. You can also search online forums where the free exchange of ideas is expected and encouraged. Target passionate people with great questions, answers, insights, and ideas, whether they are actively searching for a career change or not. Make use of smaller, industry-specific networking sites as well. Online platforms are especially helpful if you are hiring for a geographically remote position or if your company is new and is not yet well-known.

Interesting conference and seminar speakers. Maybe these expert speakers are ready to get back in the game. Even if they aren’t, they meet qualified people who are literally obsessed with your industry on a daily basis. What better source for inspired, ongoing referrals?

Trade show exhibitors. You know them. Those dynamic people you see in action, and know immediately that you want them on your team. Be discreet and professional, but make sure you get their card, and let your interest be known as soon as possible.

Trade show attendees. Applicants can (and will) feign interest in an interview. At trade shows and similar events you have the rare opportunity to target individuals who are displaying obvious interest in your field. No one gets out of bed at 5am on a Saturday to attend a lecture on cheese-making unless they really love making cheese.

Followers on social media. They’ve already done you the favor of “liking” you on social media. Show them a little interest right back. One push of a button can turn someone from a passive applicant to an active one.

Online job boards. Monster represents almost 15% of US job seekers with around twenty million profiles and resumes, and those numbers are growing fast. Indeed sees 200 million visitors a month. There are thousands of industry-specific platforms on the internet. Online job boards are a valuable tool for growing your pool of candidates and you won’t want to pass them up.

LinkedIn. With over 500 million users in over 200 countries you can’t afford not to be on LinkedIn. Leverage every contact you’ve got. Your top talent has quality associates. Connect with them.

Contractors. Websites such as UpWork and Freelancer can be a great source of contract workers both locally and off-shore. This can be an excellent option for project-based work, and if things go well, you can consider offering them a permanent job when they’re done. Of course, these types of sites are best suited for work that can be done remotely, but local contract workers can often come into your place of work as well.

Recruitment agencies. There are 20 agencies that would bang down your door this very moment to be your go-to for superior talent. The question is, can they produce? How do you recruit the recruiters? If the best measure of a recruiting agency is how long quality hires stay with the company, perhaps the truth of the matter is that most recruitment companies haven’t been in business long enough to be gauged by this particular yardstick. How can we piece together an accurate picture of their value, now and in the future? Find a recruiting agency collects data at every stage of the hiring process for more useful results. A great many agencies leave a lot of information “on the table.” Insist upon measurable, quantifiable data on an ongoing basis.

Every business is unique and will use various combinations of recruitment solutions:

Canadian HR manager Stephanie Bentzen credits keeping her finger on the pulse of local hostels with her recruitment success. Bentzen staffs Vancouver’s Isadore Landscaping, and insists that contrary to public opinion, Vancouver is rife with eager recruits. They are arriving daily with 2 year work visas from countries all over the world. “You just have to know where to look. Get creative,” says Bentzen. She also relies heavily on Craigslist, relevant job boards, online forums and cultivated referral sources in various government employment offices when searching for seasonal and full-time employees. She is currently arranging a work placement and job shadow for a local grade 11 student with an Isadore foreman that specializes in carpentry, the teen’s primary interest. It seems obvious that this hiring manager has the foresight to look to the future for her next quality hire. Bentzen has benefited from thinking outside of the box when it comes to finding talented recruits.

Recruitment requires a balance of new approaches and traditional methods, and certainly much more time, delicacy, and attention than it used to. The optimal recruiting system will provide a high percentage of quality applicants and allow you to recognize them when you see them.

By maximizing your use of internal sources you will find often-overlooked candidates among personal and industry contacts. Taking advantage of multiple external resources will grow your talent pool and increase your odds of tracking down your ideal employee. Try a few angles that you hadn’t previously considered and you may find new success in sourcing and retaining great talent.