All students, including students with disabilities, participate in state accountability systems. Most students with disabilities participate in the regular assessment, with or without accommodations. Students with more significant cognitive disabilities participate in the alternate assessment based on alternate achievement standards (AA-AAS). A few states also have an alternate assessment based on grade-level achievement standards (AA-GLAS) for students with disabilities who need testing formats or procedures that are not included in the regular assessment and are not addressed with the use of accommodations. In 2007, federal regulations introduced another assessment option--the alternate assessment based on modified academic achievement standards (AA-MAS). Eligible students may be from any disability category, and they must be considered unlikely to achieve grade-level proficiency within the time period covered by their Individualized Education Program (IEP) and must have IEP goals based on grade-level content standards. The AA-MAS is an optional assessment. The National Center on Educational Outcomes (NCEO) has been tracking the characteristics of states' AA-MAS since 2007. According to the 2009 NCEO update on test characteristics, 13 states had developed what they considered to be an AA-MAS, and three states (Texas, Kansas, and Louisiana) had received federal approval. The current report found 17 states that by the 2010-11 academic school year had developed, or were developing, what they considered to be an AA-MAS, and one additional state (North Carolina) had received federal approval. All states' AA-MAS contained multiple-choice items with fewer states using constructed response items and performance task items. The current report also tracked test design changes between the AA-MAS and regular assessment. At least half of the states incorporated the following test design changes: "additional graphics", "additional white space", "distractor removed", "fewer items", "fewer items/page", "key text underlined/bolded/bulleted", "larger font size", "one column format", "segmenting of passages", "shorter passages", "simplified graphics", and "simplified language". This study also tracked whether states' AA-MAS were computer-based, whether states with computer-based tests (CBTs) included tutorial and practice test opportunities, and whether states' documents included considerations for English Language Learners (ELLs) with disabilities. Six of the seventeen states had a computer-based test--four also provided tutorials and five provided practice tests. Documents from nine states suggested that the needs of ELL students participating in the AA-MAS were considered. Appended are: (1) State Documents Used in Analysis; and (2) AA-MAS Characteristics by State. (Contains 5 figures and 9 tables.)