One reason many people find it difficult to change careers is they think they have to do it in one big leap. Another is simple inertia -- it's easier to stay with the familiar pain of doing what they don't like than brave the unknown.

But you don't have to change careers in one fell swoop. Neither does a career change have to involve suffering and hardship. You can start by taking small steps now that will lead to where you want to be professionally, without losing significant income or disrupting your family.

This transition begins with conducting a thorough self-assessment that identifies your career goals.  Once you know what you want to do, you can begin taking practical steps to land a job in this new field. Here are five ways that others have made the transition.

Build on functional skills. If you like using your core skills and knowledge, consider transferring them to another industry or field you might like more. For instance, a corporate marketing professional seeking more meaning in his work might transfer his skills to a nonprofit organization.

Identify your key functional skills, then repackage them in a resume that highlights any volunteer or taskforce work in the new field or ways your current job overlaps it. Next, start listing employers to approach and begin networking with current or past employees at these firms about possible openings.

Building on your skills lets you apply your experience and wisdom immediately and usually results in a smooth transition to a new field. The down side may be the time it takes for you to find work that's truly satisfying. Once a registered nurse in obstetrics and delivery, Kathy Kuffner is now a senior consultant with First Transitions, an Oak Brook, Ill., outplacement firm that specializes in health care.

Ms. Kuffner, 53, switched to the career industry using her functional skills, but it took about eight years to make the transition from her former profession. While she was working as a nurse, an architectural firm that designed hospitals asked her to be its liaison between the hospital staff and the architects.

Ms. Kuffner spent five years with the firm as a nurse consultant, while teaching Lamaze classes at night. Ready to do something else, she leveraged her knowledge of health care to land a job as a recruiter for a search firm specializing in health-care professionals.

After about two years, Ms. Kuffner realized that she still liked health care but wanted to draw on her coaching and mentoring skills in her daily work. "I wasn't aggressive enough for the executive-search business," she says. She began doing outplacement project work for First Transitions, then joined the firm full time. "I identified other environments where I could use my clinical nursing background," she says. "That's what made me appropriate for each one of these positions."

Start a parallel career. This strategy allows you to keep your full-time job, while working weekends or at night in a second profession. You can accomplish the same goal by volunteering. However, "parallel careering" means being paid in a second profession, says C.B. Bowman, vice president and senior counselor for Lee Hecht Harrison Inc., a New York-based outplacement firm. Earning a paycheck in the second field gives you credibility.

"The point of being paid in the second career is to identify what you're doing as a career, not a hobby," she says. "We feel it isn't worthwhile if we aren't being paid."

Working in a second profession will give you the experience you need to pursue it full time. By keeping your day job, you'll have a steady income while building your credentials. Be careful not to antagonize your primary employer, though, since companies don't always view moonlighting favorably.

"There's still that concept that you should work for only one company," says Ms. Bowman. "It's better to keep your second job to yourself, so you don't hear, `You would have done better on this project if you were focused.' "

Also take care not to deplete your energy. Neither career should be exhausting. Nor should your extra career activities detract from family responsibilities. "Be sure your family members have bought into this," she says.

Ms. Bowman was a marketing services manager for a Fortune 500 consumer products company when she began thinking about other career directions. She started to work as a private career counselor at nights and weekends and as a counselor on contract to a major outplacement firm. A few years later, after spending 15 years in marketing services, Ms. Bowman opted to take early retirement. She was hired as a career counseling professional at a New York-area outplacement firm and later joined Lee Hecht Harrison. "By the time I retired, I was well-known in the field," says Ms. Bowman. "I had several job offers."

Make an internal transition. If you want to stay with your current employer, consider making an internal job change that launches you in a new career direction. The process that leads up to landing a new position internally is called "job enrichment," says Arlene Hirsch, a career counselor in Chicago and author of "Love Your Work and Success Will Follow" (John Wiley & Sons, 1996).

"This is when you seek new learning opportunities and ways to expand your skills," she says. "You're looking at your current job and employer and how to give yourself a different identify and dimension."

Seek out chronically unfilled responsibilities -- perhaps a task others don't want to do -- and volunteer to take on these responsibilities while in your current job. You may be saddled with extra work temporarily, but eventually you may move into the new area or be promoted.

"The reason people resist this strategy is that they feel they're setting themselves up to do more without being paid for it," says Ms. Hirsch. "That's short-sighted. If the skills you learn are really marketable, you can launch a new career from it."

Identifying unfilled openings, then networking with hiring managers to show your interest and aptitude, is another way to tap internal opportunities. In 1994, Dodi Briscoe joined PACCAR Inc. [sic] a Bellevue, Wash., multinational truck manufacturer, as a benefits specialist. She administered a retirement plan for the company while doing training assignments whenever possible.

Later she was promoted to senior benefits specialist and tapped for a company mentoring program. A self-assessment conducted at the start of the program showed "in neon that what I wanted was to be helping, guiding and coaching people," says Ms. Briscoe, 44. A company executive encouraged her to apply for an opening as a management-development manager. She was hired and in July 2000, just two years later, she was promoted to her current job as PACCAR's director of organizational development. Ironically, she had earned her master's in this field 10 years earlier.

"If I had applied for this job on the outside, all I would have had was limited experience and a degree," she says. "This way, my work ethic and the quality of my work were known."

Return to school. This is a good strategy if you want to enter a new field that requires educational credentials that are radically different from your background or current degree. Michelle Walsh, coordinator for the Beaux Arts Society, the fundraising arm of the Boise, Idaho, Art Museum, wants to work in the addiction treatment field. She's now taking courses at Boise State University at night toward a master's degree in health science. With her day job and three small children, she expects the degree to take between three and seven years. "I'm in no hurry," says the 39-year-old.

Going back to school allows you to learn the new profession and gain credibility, but it can be expensive and keep you from working. For many professionals, earning a technical certificate or completing other short-term training is sufficient to qualify them for a new field, says Lynette Fairey, a division manager in Austin, Texas, for the Human Capital Consulting Group of Spherion Inc., a human-resources services firm. "Across the board, I don't recommend returning to school," she says.

Go cold turkey. Suppose you know what you want to do, but you can't stand being in your current job another day longer. For you, quitting your job outright to do the legwork required to enter a new field may be an option, especially if you have funds stashed away to support yourself during the transition. "If you hate what you do, you may need to quit your job, but don't create a double angst," says Ms. Fairey. "It's one thing to be financially successful, but quitting to change careers creates a bigger burden if you need the money."

Julie Jansen, a Stamford, Conn.-based career coach and motivational speaker, had been a high-level sales and business development executive for national outplacement firms for about eight years, rising to the post of vice president and New York office manager at her last firm. But although she earned a six-figure income, Ms. Jansen says she was "miserable."

She decided to focus on developing a public-speaking career, especially after a friend told her that "the only time I would light up was when I talked about speaking," she recalls. After doing research about this career field for a few months, she quit her job to set up shop as a motivational speaker, career coach and business consultant. "I just cut the cord," says the 40-year-old.

To generate work, Ms. Jansen had lunch with everyone she knew to tell them of her new venture. Slowly the business grew. "I started my business with no business," she says. This strategy works best for executives who are highly motivated and confident in their abilities.

"You're forced to act and it's very exciting," says Ms. Jansen, "but the cash-flow situation can be terrifying. I had a lot of stressful moments over it." Now she says she earns more than she did at her previous employer.