Although the conceptual foundations of PBS at the universal level have been widely described and presented in the literature, secondary and tertiary interventions have been presented through very limited examples. This paper defines the key features of secondary and tertiary interventions and presents a decision-making process to guide schools through a continuum of strategies at these levels. The continuum is described in terms of a recursive loop, repetitively asking four questions: what is predictable about student failure, what is the simplest effective intervention, how can consistent implementation be achieved, and is it working? With each pass through this set of questions there is a steadily increasing focus on smaller groups and eventually individual students. The focus on the continuum of strategies at the tertiary level for individual students is presented through the lens of functional behavior assessment. A summary and recommendations for future study are included.