Reflecting the EU Procurement Directives, the UK Regulations provide that where a contracting authority wishes to lay down technical specifications which must be met by the contract, then it must specify the technical specifications in the contract documents. Equal access must be afforded to economic operators and contracting authorities must ensure that no obstacles are created to opening up public procurement to competition. The EU Procurement Directives and the UK Regulations therefore generally prohibit specification of particular items that can be sourced from only one supplier and technical specifications must afford equal access to the procurement and should not create unjustified obstacles to opening up the public procurement to competition.

Bidders are not allowed to change the specifications or submit their own standard terms of business (as this would also amount to a change of specification). However, contracting authorities may permit bidders to submit variant bids and if so, should make this clear in the contract notice or invitation to confirm interest.

Some measures were codified in the PCR 2015 in order to enable greater access to public contracts by small and medium enterprises ("SMEs"). Those measures:

• ensure that a contract opportunity above or below the EU threshold is also advertised on the Contracts Finder website, when a contracting authority advertises such contract opportunity;
• require contracting authorities to have regard to Cabinet Office guidance on the qualitative selection of economic operators for above threshold procurements to prevent SMEs from being asked burdensome or unnecessary questions;
• remove a pre-qualification stage for below threshold procurements; and
• improve prompt payment, by requiring contracting authorities to include provision for 30-day payment terms that flow through the supply chain.

The measures either remove unnecessary barriers to participation, or reduce time and cost in procurement procedures.