Today's educational environment requires teachers who understand teaching and learning, have strong content knowledge, and can make connections between life experiences and the curriculum. Teachers are expected to be continually learning to improve their practice. Professional learning is essential in this process. Research on professional development practices in various school contexts shows how teachers can improve and develop better instructional practices through a variety of learning experiences. Sadly, very little research exists on professional development practices of private Christian school teachers. This study explored professional development practices of Christian school teachers in nine evangelical Christian schools in the Detroit, Michigan, area. This study explored Christian school teachers' professional development experiences using a mixed-method multi-case study approach. I used the National Staff Development Council's (NSDC) Standards Assessment Inventory (SAI), which focused on 12 professional development standards: (a) learning communities, (b) leadership, (c) resources, (d) data-driven, (e) evaluation, (f) research-based, (g) design, (h) learning, (i) collaboration, (j) equity, (k) quality teaching, and (l) family involvement. I also collected qualitative data from teacher focus-group interviews and written reflections to discover themes and patterns in their professional processes, growth, and learning. I surveyed nine evangelical Christian schools and 171 teachers participated. Three of the 12 standards that emerged with the highest means were equity, leadership, and family involvement. The three standards that were ranked the lowest were evaluation of professional practice, data-driven professional learning practices, and professional learning communities. In focus groups and written reflections, teachers reported many sources of professional learning, ranging from parental, school, and college influences as children and youth, to faith development aspects, to personal experiences, including parents, travel, dialogue, and reading. They reported their Christian "walk" was a sustaining force in their own professional development. They sought teacher networks, graduate education, and training via the Internet as places for growth. They also reported utilizing more traditional learning methods (e.g., generalized book discussions and workshops) and informal, individual professional means (e.g., daily experiences and faculty conversations) of learning. Teachers believed their educational leaders had strong beliefs about the importance of teacher professional learning and articulated a shared commitment to professional growth, but often designed broad professional learning activities, while most teachers preferred content specific professional learning tied to effective teaching strategies. Teachers reported strong leadership was lacking and wanted their leaders to be better role models of professional growth and learning. Together, the survey and qualitative data indicated many positive learning elements were present as listed above (supportive leadership, family involvement, personal experiences, etc.). Some elements, however, were missing. There was not a culture where teachers observed and gave feedback to each other, nor was there regular data collecting and sharing nor data-driven decisions and shared assessments. One area uniquely present but not always indicated in the general professional development literature was the role of teachers' Christian faith in guiding and inspiring personal and professional learning. These teachers considered themselves "called" to nurture their students' faith and learning. This commitment to God and his children motivated them to become the best teachers possible. The Christian school teachers developed professionally: (a) through traditional professional development practices, (b) by daily, job-embedded classroom and professional experiences, and (c) informal professional learning experiences, but needed more, well-planned, professional development opportunities that were content specific and allowed them to collaborate or network with other teachers, particularly from other Christian schools. They also received support to attend conferences and workshops and complete advanced degrees, and extra time during the school day to use student data to make collaborative decisions. School leaders should (a) create professional development funding in their budgets, (b) plan quality professional learning activities in cooperation with teachers who have content-rich and relevant strategies, (c) share current literature on quality and effective professional practices, (d) model life-long, professional learning, and (e) encourage informal, teacher-directed learning that includes experimentation and reflection. More research could explore the quality and effectiveness of professional learning experiences, especially the role of informal, teacher-directed learning, and the role and professional learning of school leaders in the development of professional learning communities at Christian schools. 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