There is a high incidence of non-contact anterior cruciate ligament (ACL) injury in team sports, especially among adolescent females. This injury is associated with an increased risk of developing osteoarthritis later in life and a decrease in lifetime physical activity. Traditionally, return-to-sport (RTS) programs following ACL injury have focused on restoring the athlete's general health and tissue healing. We will propose a framework that views RTS as a two-part process: first, recovery of general health after ACL reconstruction (ACL-R) (rehabilitation) and then return to competition (RTC) after ACL-R, all of which occurs on a continuum. The objective of Part I is to stablish the foundation to propose an evidence- and experience-based guide on RTS following ACL reconstruction in athletes participating in team sports, specifically for later phases. First, we describe the causes of and risk factors associated with ACL injury. Next, we describe the specific characteristics of team sports that predispose athletes to ACL injury. Finally, we present a progressive framework to successfully return athletes to a pre-injury level of competition that also minimizes risk of reinjury. In Part II we will focus on how to put the proposed framework into practice when return team sport athletes to play following ACL-R.