Abstract:The two-twistor formulation of particle mechanics in D-dimensional anti-de Sitter space for D = 4, 5, 7, which linearises invariance under the AdS isometry group Sp(4; K) for K = R, C, H, is generalized to the massless N -extended "spinning particle". The twistor variables are gauge invariant with respect to the initial N local worldline supersymmetries; this simplifies aspects of the quantum theory such as implications of global gauge anomalies. We also give details of the two-supertwistor form of the superparticle, in particular the massive superparticle on AdS 5 .