Maria T. Codina Leik, MSN, ARNP, FNP-C, AGPCNP-BC, is the president and principal lecturer at National ARNP Services, Inc. (npreview.com). Well known for her ability to simplify complex concepts for her students, she is a popular speaker and educator. Ms. Leik taught previously in the nurse practitioner (NP) program at Florida International University Graduate School of Nursing. She is board certified by the American Nurses Credentialing Center (ANCC) and the American Academy of Nurse Practitioners Certification Board (AANPCB) in two specialties: family NP and adult-gerontology primary care NP. She is an experienced NP with more than two decades of clinical practice. In addition to her two NP certification review books published by Springer Publishing Company, Ms. Leik is the author of chapters in two NP textbooks and is a member of Sigma Theta Tau International Honor Society of Nursing.