The National Professional Development Center on Inclusion (NPDCI) is a project funded by the Office of Special Education and Rehabilitative Services of the United States Department of Education. NPDCI is charged with working with states to develop a quality, integrated system of professional development for early childhood personnel. NPDCI has proposed the following definition of professional development for early childhood which we have adapted for use in our project as follows:
"Professional development is ongoing interactive teaching and learning experiences designed to support learner's acquisition of knowledge, skills, and beliefs/values as well as the application of these in practice to benefit children and families."

According to NPDCI, the key components of professional development include:
(a) the characteristics and contexts of the learners (i.e., the "who" of professional development, including the characteristics and contexts of the learners and the children and families they serve);
(b) content (i.e., the "what" of professional development; what professionals should know and be able to do; generally defined by professional competencies, standards, and credentials); and
(c) the organization and facilitation of learning experiences (i.e., the "how" of professional development; the approaches, models, or methods used to support self-directed, experientially-oriented learning that is highly relevant to practice).

National Professional Development Center on Inclusion. (2008). What do we mean by professional development in the early childhood field? Chapel Hill: The University of North Carolina, FPG Child Development Institute, Author.