A process for preparation of potassium clavulanate by the direct precipitation of clavulanic acid as the potassium salt by providing a solution of clavulanic acid in an organic solvent and mixing a potassium salt with this solution, with between 0.1 % v:v and 7.5 % v:v of water present in the region where the clavulanic acid and potassium salt contact, then isolating the so-formed potassium clavulanate.