Generally you have three main options depending on the circumstances
Leave your benefits in your existing pension arrangement (preservation of benefits)
Transfer your benefits to your new arrangement (transfer of benefits)
Take a refund of contributions in limited circumstances (refund of member contribution)
Preservation of benefits
If you're a member of a company pension plan (or an occupational scheme as it can be called), when you leave your job, you won't be a member of that scheme anymore.
If you were part of the company pension plan for 2 or more years, you can leave your pension in that scheme until you retire. Those benefits will be held for you and you can claim them when you draw your pension.
Transfer of benefits
If you were a member of a company pension plan (or occupational scheme) you can:
Transfer your pension into a PRSA
Transfer your pension to another company pension plan (if you're joining a new company and they offer pension), a personal retirement bond, or there are overseas transfers also available.
If you already have a PRSA, and you want to join a company pension plan you can also transfer your PRSA contributions into your company pension plan.
Refund of member contribution
If you are in a company pension plan, and you are leaving the company before two years of service, you might be obliged to take a refund of your pension contributions. Some employers will allow you to keep your contributions in the scheme, some may not. This will depend on your employer.
When you have been employed for less than two years with that company, you can also choose to take your pension contributions with you. If your employer contributed to your pension, they are also entitled to retain their contributions if you are with the company for less than two years. Whether they do this or not is dependant on your employer.