Catherine I. Tantau, BSN, MPA, President, Tantau & Associates, is an internationally recognized authority on access, efficiency, and flow systems in health care. Her extensive experience includes designing and implementing demand management models with a special emphasis on utilizing health care workers in fully expanded roles. She led the creation and implementation of Advanced Access and developed the Access and Office Efficiency Internal Collaborative Model. Ms. Tantau has worked with hundreds of health care organizations in the US and Europe using this model to improve access and medical office flow. She has chaired and been faculty for the Institute for Healthcare Improvement's national Waits and Delays Collaborative, and she was advisor to the UK National Health Service Cancer Care Access Initiative. She has published widely in peer-reviewed journals and speaks internationally on various health care topics.