Firms are running out of options to hire staff amid a continued shortage of skilled workers, according to a new report.
Research among 600 employers found that four out of five planned to take on more permanent staff in the next few months.
Most businesses were operating close to full capacity and half have given staff a pay rise in the past year to help retain employees, said the Recruitment and Employment Confederation.
Chief executive Kevin Green said: "Options are running out for organisations that want to take on more staff. Schools and hospitals are already facing enormous problems because of a shortage of teachers and nurses.
"The need for people to do the jobs available is driving firms to become more innovative and creative in their recruitment strategies.
"As campaigning begins in earnest around the EU referendum, jobs will be high on the agenda. We urge both sides of the argument to keep in mind that UK businesses must have sufficient access to the global labour market in order to thrive.
"We need more skilled people to fill job vacancies in the UK, not fewer."
Almost four out of five employers said economic conditions were improving, slightly down on surveys at the end of last year, while around one in five said things had worsened - almost double the figure in September.
Skills shortages were particularly affecting technical and engineering jobs, said the report.
Employment Minister Priti Patel said: "Our record-breaking employment is being fuelled by full-time work. With wages continuing to grow and a record 776,000 vacancies waiting to be filled at any one time, it's clear that confidence has firmly taken hold in the labour market."
Mick Cash, leader of the Rail, Maritime and Transport union, said: "Britain's growing skills shortage threatens to undermine and delay key transport infrastructure projects and can be wholly blamed on a chronic lack of foresight and joined up thinking when it comes to workforce planning.
"We need a major expansion of apprenticeships and training and a move away from the kind of casualisation and short-termism that has blighted the transport sector for far too long."