This study examines how critical mathematical literacy teachers conceptualize their practices and how those practices were demonstrated in the classroom. Practices were considered from an ontology of mathematics education, specific to critical mathematical literacy, in which classroom interactions question what it means to do mathematics as an individual, as a citizen, as a community member. The study adopted an ethnographic study of three participants who self-identified, or were nominated by colleagues or peers, as critical mathematics secondary school teachers. The emphasis focused on understanding the core values and beliefs of these teachers to better comprehend how this subculture conceptualizes critical mathematics literacy (CML) practices. Analysis took particular note of the nature of strategies used for CML instruction, as well as means for developing an understanding of the meaning of participants' classroom actions. Critical mathematical literacy was interpreted as six domains of mathematical understanding that prepare students to explore their life situations through an understanding of how mathematical comprehension of social and moral decisions can lead to transformative social change. [The dissertation citations contained here are published with the permission of ProQuest LLC. Further reproduction is prohibited without permission. Copies of dissertations may be obtained by Telephone (800) 1-800-521-0600. Web page: http://www.proquest.com/en-US/products/dissertations/individuals.shtml.]