Transmission electron microscopy has been used to investigate point defect aggregates which were resolvable as dislocation loops in neutron irradiated and annealed molybdenum. The so-called formal analysis was employed in determining the direction and sense of their Burgers vectors. In foils containing a wide spectrum of loop sizes, both vacancy and interstitial type loops have been identified with Burges vectors of the type a/2⟨111⟩.