Today, school climate assessment has become an increasingly important and valued aspect of district, state, and federal policy. Recognizing that effective school climate improvement efforts are grounded in valid and reliable data, the Federal Department of Education launched the Safe and Supportive Schools grant in 2010 to provide 11 states with federal assistance that supports the development of rigorous school climate measurement systems. An essential step to school climate improvement is gaining a clear understanding of each school's particular strengths and potential areas of need through an iterative, data-driven process of feedback from the entire community--students, parents/guardians, school personnel, and ideally the wider community members. This data then becomes a springboard for a collaborative, community-wide process of improving the school climate, and creating targeted action plans and sustained efforts focused on the areas that will most benefit the school. Choosing an effective school climate instrument can be challenging. However, there are a number of essential factors to consider when determining the assessment tool that best fits a particular school's needs: (1) A strong research-base; (2) A strong, vigorously tested track record; (3) An instrument that measures core populations; (4) Ease of administration; (5) Additional features that fit the particular needs of each individual school community; and (6) Guidelines and useful tools to assist in understanding, and use of the tool. Strategies to guide effective practice are also discussed.