Up until recently there was no legislation that actually required employers to provide or make any pension provisions for their workers. Employers had complete discretion over whether they provided a pension or not (a decision based most likely on an ability to pay).
This however has changed due to the implementation of the Pensions Acts of 2008 & 2011, and starting in October 2012 with large employers first, there will be a compulsory scheme in place that will require ALL employers to automatically enroll all their eligible workers in a workplace pension scheme AND make minimum financial contributions to that pension. These measures will then be progressively introduced, such that it will be more likely 2015 - 2018 for small employers with less than 30 workers. You will be contacted by The Pensions Regulator, approx.12 months prior to your auto-enrolement staging date (or you can check your start date by contacting us).
This is VERY complex and you can't ignore it.
We have prepared the following Guide to give you further information on the Auto-enrolment pension scheme.