Instructional coaches are former teachers or principals that have shown effectiveness in their work of teaching or leading and go through additional training to learn more about the technical skills needed to be an effective coach. In her book "The Art of Coaching", Elena Aguilar recommends that a coach "must have been an effective teacher for at least five years". Although skills that were effective in the classroom are required, the coach must also be confident in working with adults and bring strong listening, communication, and data analysis skills to the coaching position. Ultimately, an instructional coach is a former teacher who was successful in the classroom and is respected in the field, with the respect carrying over into this new position.