An internal coach is an employee of the company wherein they provide coaching services to other employees. An external coach is hired as a business service provider, whether an individual in business as a coach or an organization in the business of providing coaching.
Note: The American Management Association published a study that indicates internal coaching programs within companies are most effective when the internal coaches have external training, when the internal coaching is offered to all employees and the internal coaches work with them up through middle management, and the executive leadership has external coaches.
As an individual looking for a coach, the process often starts with asking for a referral, searching on LinkedIn, through networking, or by using an online directory of coaches.
When a company wants internal coaches they identify employees to train – most often from the Human Resource or Training and Development departments.
When a company is hiring an external coach they will source them through referrals, find them through published books on Amazon, use LinkedIn, or research organizations that are in the business of providing coaching services.