Self Invested Personal Pension (SIPP)...
SIPPs come under the same basic rules as far as contributions, tax relief, eligibility etc are concerned. However the difference arises out of what the investments underlying the arrangement can consist of.
A conventional personal pension generally involves the plan holder paying money to an insurance company for investment in an insurance policy. This means the money is invested with relatively little choice or freedom from the plan holder.
A SIPP allows the plan holder much greater freedom in what to invest in and for the plan to hold these investments directly. The SIPP holder can have control over the investment strategy or can appoint a fund manager or stockbroker to manage the investments.
For SIPP contracts written under trust, the trustee controls the investment under instruction from the member. It is possible for the plan holder to be the trustee. If this is the case, an approved administrator must be appointed to carry out investment transactions.