This sequential mixed methods study examined Head Start professionals’ use and conceptions about Teaching Strategies GOLD (TS Gold) assessment system in the Northeastern U. S. We conducted 17 interviews which then informed a survey (N = 153). We analyzed all data sources together, with three primary findings. Professionals endorsed recommended uses of TS Gold. The demands of using TS Gold often outweighed resources available to Head Start professionals, especially teachers. Respondents with a background in education or in a teaching role used TS Gold more, and those who generally agreed that assessment improves educational outcomes also reported more positive TS Gold conceptions. (author abstract)