The Texas Success Initiative (TSI) is mandated by Texas law to ensure that students enrolled in Texas public colleges possess the academic skills needed to perform effectively in college-level coursework. TSI includes a testing component designed to identify and provide diagnostic information about the reading, mathematics and writing skills of each student. Note: All students subject to the TSI requirement must take the THEA, or an alternative TSI assessment test. If an assessment test is required, the scores must be recorded by Lamar University before advising and registration.