Theories of mentoring help workers expand their understanding of the company or the industry so they can increase productivity and work on personal development. Some mentoring styles involve top-down advising and others put mentors and mentees on similar ground. One-on-one and group mentoring styles help new or novice employees learn about the company culture, understand business protocols and build strong customer relations from more experienced or more knowledgeable managers and coworkers.

Long-Term, Top-Down Mentoring

Top-down mentoring, also known as executive mentoring, is an effective way to increase and improve industry knowledge and work skills, according to Management Mentors, a Massachusetts-based organization devoted to teaching businesses how to mentor talent. This theory requires a senior-level employee to teach, instruct, coach or guide a subordinate. As an executive mentor, you'll likely work one-on-one with your subordinates, but you may have more than one mentee at any given time. The goal is to help your subordinates understand the company culture, gain knowledge about the industry and develop their work skills. For example, you might invite your mentee to attend meetings with you, visit clients together or review and assess reports together. Work-related lunch outings provide a way to converse privately about business dealings outside of the office. Management Mentors states that executive mentoring is advantageous because it equips workers to fill senior-level positions when management retires.

Short-Term, Training-Based Mentoring

Some companies organize in-house training sessions or have their employees attend industry-specific training seminars to help them learn about new technologies, improved practices or up-and-coming business strategies. A mentor is assigned to a mentee to help her develop the skills that are being taught in the training program. This top-down mentoring approach is very specific because it's a short-term assignment that only lasts as long as the training and immediate follow-up. Even though this type of mentoring is effective at helping mentees learn a new skill or practice, it doesn't help them develop a larger, broader skill set.

Peer Mentoring

Peer mentoring is when a more experienced worker advises a newcomer or a less experienced worker, but both have similar titles, roles and responsibilities at the company. You can engage in peer mentoring one-on-one or in a small group of four to six workers. This theory works well for the Millennial generation because they generally have more than one mentor and they require extensive amounts of feedback, suggests Forbes. Peer mentoring puts mentors and mentees on similar ground, making discussions more approachable and encouraging two-way communication.

Reverse Mentoring

Reverse mentoring is a theory and practice that encourages younger, less-senior employees to mentor their managers or supervisors. This type of mentoring works well with the Millennial generation because they are tech savvy and know how to use social media to increase business communication. For example, a junior-level employee -- fresh out of college -- can help a 60-year-old manager learn how to use a social network, such as Twitter, to promote a new product or service. Or, he can show him how to use LinkedIn to connect with other business professionals in the same field. Wendy Marcinkus Murphy, associate professor of management at Babson College in Massachusetts, says that reverse mentoring is a way to "bridge the generation gap and create a two-way exchange of knowledge," according to the AARP article, "Boomers, Millennials Reverse Mentoring Roles."