This mixed-methods, survey research explores the impact of instructional coaching in a mid-sized California school district on teacher efficacy, as assessed in part by Tschannen-Moran and Woolfolk Hoy's (2001) "Teachers' Sense of Efficacy Scale." Literature highlights instructional coaching activities, roles, and supports that can positively impact teachers. Research also identifies instructional coaches have the greatest impact when developing collaborative, trusting teacher relationships. Significant findings between perceived use of instructional coaching and teacher efficacy in classroom management, student engagement, and instruction are indicated. The paper includes implications for intentional use of instructional coaching with novice teachers to increase efficacy and how differentiation of instructional coaching with veteran teachers might increase value of the coaching process for this subgroup.