The RISLUS Multilingual Syntax Test (RMST) assesses comprehension of complex syntactic structures in six languages (English, Spanish, Mandarin Chinese, Arabic, Japanese, Russian). Based on developmental milestones in acquisition, such as relatives clauses and sequence clauses, this test measures syntactic knowledge that is a pre-cursor to fluent reading beyond the sentence level. It is ideal for pre-literate, young children, or individuals without formal school in the language. The test is available on paper and, online, and has been adapted for use with an eye tracker.