We study approximating partial orders with projections (approximating pop's). These are triples (D,≤, P) consisting of a poset (D,≤) and a directed set P of projections such that the supremum of P exists and sup P = idD. We derive a canonical uniformity U on D and relate properties of U such as completeness and compactness to properties of the poset and the projection set. We show that each monotone net in D is convergent if and only if (D,≤) is an algebraic domain such that the images of the projections are precisely the compact elements of (D,≤). Furthermore, the bifinite domains arise exactly as approximating pop's where U is compact.