As state governments get ready for the Affordable Care Act coverage expansion, some are taking a close look at their networks of health care professionals to make sure they will be able to meet increased demands as more people gain health insurance. California is one of 15 states expected to consider legislation this year that would give advanced practice nurses more independence and authority. Tina Clark is a nurse practitioner at Glide Health Services, a clinic in San Francisco's Tenderloin district, a low-income section of the city. Glide is run by nurses with advanced training. A physician visits the clinic 12 hours a week, to sign forms and consult on difficult cases.