When nurse practitioner JoAnn Woodward began her career,a registered nurse had to take your blood pressure. ''Now,'' she says, ''Rite-Aid takes your blood pressure–and a nurse [practitioner] can evaluate your pap smear or [perform early cancer detection by] colposcopy. It's a great time to be a nurse.''

Today, nurses with advanced degrees and/or certifications act as specialized consultants in tandem with physicians and other nurses. They head nurse-run clinics. They act as primary-care providers. Many operate their own private practices.

As a result, nursing is a more diverse and rewarding career than ever. And many believe more positive changes are on the way.

''We've seen an explosion of interest among consumers who want to be involved in their own care,'' says Andrea Lindell, president of the American Association of Colleges of Nursing and dean of the University of Cincinnati's School of Nursing. ''Nurses trained to promote health–and not simply treat disease–are in a unique position to facilitate that interest.''

Changes in the health-care system also promote opportunity. The dean of UCLA's school of nursing, Marie J. Cowan, explains, ''In a managed care setting, where physicians may be required to see x-number of patients in an hour–and hospital stays are shortened–the role of the nurse practitioner becomes vital. HMOs see nurse practitioners as [being able to provide] cost-effective managed care.''

Many nurses, such as JoAnn Woodward, pursue advanced practice to enjoy greater career satisfaction. She's operated her own women's health practice, Seaside Women's Services, in Manhattan Beach since 1979. For the entrepreneurial Woodward, autonomy is its own reward.

''I like to do things myself,'' Woodward explains. ''I like being able to see patients when I think they want to be seen [such as evenings and weekends]; I like being able to spend a little more time with my patients, to get to know them as people,'' without having to answer to policy-minded supervisors or cost-conscious administrators.

Getting the expanded training and education needed to become an advanced practice nurse takes some skill and commitment. Candidates with nursing degrees and experience have a definite edge, though requirements vary and some schools offer programs for students without nursing backgrounds.

In any case, instruction for the certified nurse practitioner generally concentrates on becoming a primary care provider, while the clinical nurse specialist focuses on developing expertise within a specific clinical area of advanced practice.

According to Cowan, certified nurse practitioner training is in particular demand–unfortunately, often at the expense of the clinical nurse specialist (CNS). ''In the hospital industry, there has been an increasing emphasis on cost-efficiency, and CNS roles were among the first to be cut,'' Cowan explains.

UCLA still trains nurses to become clinical nurse specialists–in a program that shares core curriculum with nurse practitioner candidates. But Cowan reports the majority of students seeking advanced education opt for nurse practitioner training. In fact, UCLA also offers a one-year post-graduate program appropriate for the clinical nurse specialist who wishes to become a certified nurse practitioner.

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In addition to enjoying a growing field of opportunity, a nurse practitioner generally earns higher salaries that the clinical nurse specialist. According to the Department of Health and Human Services' 1996 National Sample Survey of Registered Nurses, nurse practitioners nationwide earned an average annual salary of $54,182, compared to $47,160 for clinical nurse specialists. Salaries in California tend to be higher overall. Cowan says most new UCLA nurse practitioner graduates land jobs in the $60,000 to $70,000 range.

Some have even suggested combining the roles of nurse practitioner and CNS as a way to enhance the marketability of both. But widespread agreement over revised duties has been elusive, and a new, expanded role would likely mean significant retraining for nurses on both sides of the equation.

None of which suggests that being a clinical nurse specialist is a liability. Rather, says Cowan, career advancement is a question of flexibility. ''I know a CNS who [functions as] a nurse practitioner for a cardiology group–prescribing diagnostic tests and performing triage by referring patients to whichever doctor she thinks is most appropriate.''

Elissa Brown, vice president of the American Nurses Association in California and a practicing clinical nurse specialist in the Los Angeles area, enjoys the varied challenges of her job. As a hospital-based psychiatric and mental health CNS, Brown sees patients directly and consults on interdisciplinary teams.

''For example, if a cardiac patient is also schizophrenic, I may be called in to help determine how to treat that patient effectively in light of both his medical and psychological condition,'' Brown says. ''As a result, every day is different; there isn't a lot of routine, which suits me well.''

Across the scope of advanced practice nursing, keeping pace with new and existing challenges will remain an ongoing–and gratifying–task for all. Because, as JoAnn Woodward notes, ''I can probably list a breakthrough for every year I've been doing this.''