More than one in four firms employ someone on a zero-hours contract, the practice which has sparked controversy in recent months, a new study has found.
Research by the Recruitment and Employment Confederation (REC) among 600 employers showed that 27% used zero-hours contracts, under which people are not guaranteed work from one week to the next.
A recent report has suggested that up to a million workers in the UK are employed on zero-hours contracts, leading to Labour holding a special summit this week to discuss any abuses in the system.
REC chief executive Kevin Green said: "Zero-hours contracts are just one example of employers using flexibility to meet fluctuations in demand to ensure that their businesses survived the recession and that they kept their staff in work.
"The soaring success of the UK jobs market is a direct result of businesses successfully adapting to the challenges faced in the recession.
"As this month's figures show, flexibility has enabled our labour market to flourish. Employers are growing increasingly confident in the UK economy and making positive hiring decisions as they look forward to next year."
The study also showed that most employers plan to increase or maintain their permanent or agency staff over the next year.
TUC general secretary Frances O'Grady said: "With so many jobseekers chasing too few vacancies, zero hours contracts have become the easy option for employers keen to keep their costs down as they take advantage of people's desperation to find work.
"But while employers are singing the praises of zero hours, the experience of those actually employed in this manner is hardly a cause for celebration. Uncertain hours and fluctuating pay levels all make for a situation where it becomes almost impossible for individuals to budget and can cause havoc with childcare arrangements.
"If we are to build a strong and sustainable recovery which benefits working people, then we need to be creating secure jobs on proper contracts with decent rates of pay."