This chapter presents valid and reliable assessment tools used in therapeutic recreation to evaluate individuals’ physical, cognitive, social, and emotional functioning. The use of standardized instruments in the planning, implementation, and evaluation phases of therapeutic recreation ensures evidence-based practice and facilitates the delivery of individualized services. The chapter introduces tools that measure leisure attitudes, motivation, satisfaction, and constraints, as well as those assessing functional abilities and leisure independence. It also includes specific assessment batteries and tests applicable to individuals with developmental or special needs. Within this scope, instruments such as the Leisure Diagnostic Battery (LDB), Leisure Motivation Scale (LMS), Leisure Satisfaction Scale (LSS), Comprehensive Evaluation of Recreation Therapy Scale (CERT), Functional Assessment of Characteristics for Therapeutic Recreation (FACT-R), Leisure Competence Measure (LCM), and Well-Being Index (WBI) are described in detail regarding their structure, administration, and psychometric properties. Recognition, adaptation, and dissemination of these tools are essential for the scientific advancement of therapeutic recreation in Turkey.