A dynamic purchasing system (DPS) is a fully electronic procurement arrangement that any qualifying supplier can join at any time during its life. Buyers run competitions among the admitted suppliers whenever they have a specific requirement.
Unlike a closed framework, a DPS stays open for new entrants throughout its duration, so suppliers are not locked out if they miss the initial call. This makes a DPS well suited to categories with changing supplier markets or frequent, varied purchases.
For a smaller supplier this is usually the friendliest route into a buyer. Admission is a qualification exercise rather than a competition, you meet the stated criteria and you are in, and it can be done at a quiet moment rather than against a deadline. The work then arrives as individual competitions among admitted suppliers, often with shorter timescales than a full open procedure. The practical requirement is responsiveness: DPS competitions can appear at short notice, so your qualification documents and standard responses need to be ready before the first one lands.