Many of us dream of leaving our humdrum jobs to work in more fulfilling fields.

But making the leap can be a frightening prospect. Turning your hand to something new usually means leaving behind the financial and emotional security of your boring, but well-paid, job.

There is another option, however. An increasing number of Australians are developing portfolio careers in which they undertake work in a range of sectors, both for variety and to broaden their experience.

Michelle Jakubauskas, a researcher with Sydney's Workplace Research Centre, says that the number of people holding multiple jobs has surged in recent years. "We have a very tight labour market and there's a skills shortage, so people feel more confident about leaving a job," she says.

The most recent figures show that between 1996 and 2002 the number of people holding multiple jobs rose 4 per cent to 6 per cent and it is believed the trend has continued.

Part of the attraction of combining different jobs is the spark it can bring to a mundane working life.

Annemarie Cross, a career-management specialist with Advanced Employment Concepts, believes there are good reasons why someone might want to have two or more jobs. "You can really enjoy the variety, flexibility and freedom that come from having different professions," she says.

If you are clear about your objectives, a portfolio career can enhance your work skills. "People need to ask themselves why they're choosing a portfolio career," Cross says. "Is it to gain experience in other areas, for example? That way, they can choose their projects strategically so that they are adding value to their skills and competencies."

Some people are attracted to the idea of a better work-life balance. "People can choose how many projects they take on," Cross says. "But you must know your limitations and remember to make time for yourself and your family and friends."

Alma Gonzalez combines a part-time job as a disability support worker with her own feng shui consultancy. After six years of working in community care, Alma started studying the Asian design practice with the hope of starting her own business.

"I had always been interested in feng shui and then I came across the Australian College of Environmental Studies," she says. "I studied part-time and completed a certificate in feng shui and geobiology, and a certificate in Chinese astrology."

Portfolio careers need to be managed properly to protect your career prospects. There's the risk of losing career momentum, not being available for promotion and not earning higher salaries.

Cross says organisation is the key. "People with multiple jobs must be organised or it could be easy to get overwhelmed," she says. "Portfolio careers aren't for people who aren't organised and don't have a plan."

The experience of combining work and study helped Gonzalez juggle two very different careers. She looks after people in residential care and takes care of all of their domestic needs. "It's hard work and some days are very challenging," she says. "I get very tired. But I don't find it difficult balancing the two."

Corporate psychologist Dr Timothy Sharp says if you're planning a portfolio career, you need the right skills. "You need to be able to manage priorities, set boundaries, manage your own work-life balance and manage your own schedule," he says. "Some people enjoy it but others may find it difficult."

Sharp has found that portfolio careers aren't for everyone. "[They] work extremely well for some people and not so well for others," he says. "Some people feel split between too many things. Others love the freedom and flexibility. The challenge is helping the right people find the right path."

Gonzalez says launching a consultancy was a long process that required commitment. "When I started out I did some cases free of charge to get experience and build up my clients," she says.

Many people use portfolio careers to move to a career that allows them to gain experience and continue to earn money. The long-term goal for Gonzalez is to keep building her feng shui business. "I'd like the consultancy to be my main occupation," she says. "That's where I hope to go."

Cross has helped many clients make the transition and advises people to be realistic. "You need to understand how much money you'll need to support yourself. You need to talk to your employer about down-scaling your job and going part-time."

Part-time jobs provide the freedom to pursue another career but there are drawbacks. Cross warns that you might miss out on making workplace friends. "This can be a real downside if you're someone who likes to connect with other people."

And if you have a part-time job, you might find that your hours are severely limited.

According to Jakubauskas, workplace research has found that "people in full-time employment are working overtime, while people in part-time employment are only able to work a limited number of hours".