Topics in PEN address the broad spectrum of practice in nutrition and dietetics including institutional care, primary health care, public/community health, consulting/private practice, food service management, professional education, food and the pharmaceutical industry and government. Recognized authorities on each topic or Knowledge Pathway addressed in PEN contribute to the identification of relevant literature from filtered and original sources and critically appraise, grade and synthesize that literature into key practice points or answers to practice questions. Additionally, best practice client and professional resources and other tools that are congruent with the evidence are included in PEN to support practice, along with standard Knowledge Pathway tools including backgrounds, evidence summaries and practice guidance summaries. As new science emerges, components of a Knowledge Pathway are updated in a timely way to ensure practice guidance always keeps in-step with change. Each Knowledge Pathway undergoes a complete review at regular intervals.