There is a consensus in the behavioral literature that treatments based on the results of a functional assessment are more effective than treatments that are selected arbitrarily (e.g., Carr & Durand, 1985; Paclawskyj, Kurtz, & O'Connor, 2004). By identifying the functional reinforcers that maintain problem behavior, practitioners can design interventions that are more efficient (i.e., it narrows the list of potential interventions to choose from) and more effective. Linking treatments to functional assessment results has become standard clinical practice and has found its way into the language of federal and state legislation. This has been a positive and robust change in the behavioral intervention process. While the concept of linking treatment to function has logical appeal, practical issues arise when implementing these strategies in applied settings. In many cases, staff and caregivers may not know how to link assessment to treatment or the main components of effective function-based intervention. In other words, some care providers may complete a functional behavioral assessment (as is often required by law), but the assessment not translate into a function-based intervention due to a skill deficit on the part of the practitioner designing the intervention (i.e., they do not know how to select an appropriate treatment based on the results). Furthermore, the implementation of treatment may be affected by the level of training and expertise among direct care staff members and on-site supervisors. In many applied settings, direct care staff often do not receive proper training to effectively implement behavior intervention plans. In some cases, the primary procedure for training a staff member is to provide them with a written description of the procedure (i.e., the behavior plan). These concerns about the adequacy of staff/caregiver can have significant deleterious effects from a clinical standpoint, as improper implementation may result in negative outcomes for, not only the learner, but for staff and caregivers as well. Other practical implementation issues may involve the way treatment effectiveness is evaluated itself in applied settings. A thorough analysis of the maintaining mechanisms of the problem behavior is the cornerstone of the intervention, but uncovering functions alone is not enough to ensure an effective intervention. The real life challenges presented by implementation can be addressed with judicious assessment, sensitive treatment, and systems analysis. In many cases, treatments are evaluated using a wait and see approach, where practitioners tell direct care providers to implement an intervention and hope for a positive outcome. Taking a no is good news approach to intervention is not particularly systematic and likely leads to the propagation of ineffective intervention practices. The current manuscript will briefly review information related to the use of functional assessment procedures and common intervention strategies for different functions of problem behavior. We will then discuss some of the barriers to effective treatment implementation, particularly issues related to staff/parent training and systems issues as they relate to evaluating the effectiveness of treatments Functional Assessment The purpose of a functional assessment is to determine the cause, or the function, of challenging behavior. There are three primary types of functional assessment: indirect models (e.g., interviews, rating scales), descriptive analysis (e.g., ABC data), and functional analysis (e.g., environmental manipulations). These procedures are used to determine the antecedents that trigger maladaptive behavior and the reinforcement contingencies that maintain the behavior. Operant behavior can be categorized as being mediated by social reinforcement or automatic reinforcement. Socially-mediated problem behavior can be divided into social positive and social negative reinforcement. …