By drawing on observation and detailed discourse analysis from interviews with teachers in Lithuanian and North American schools, this text identifies individual, school-specific, and national factors which impact teachers' informal professional learning. Addressing multiple layers of teacher learning, this text illustrates how factors including socio-economic status, individual learning style, cultural attitudes to education, and political histories support or impede workplace learning. Drawing on three fields of research-teacher education, cultural anthropology, and comparative international-the book posits teacher learning as a multidimensional socio-cultural process. Finally combining a typology of informal learners with other policy-driven factors, the text indicates how practices at school, district, and national levels might stimulate workplace learning. Offering methodological innovations including unique research design and creative ways of using discourse analysis, this book will be of particular use to researchers and doctoral students in education, organizational and educational psychology, cultural anthropology, management, and beyond.