Catalytic hydrophosphination of terminal alkenes and dienes with primary phosphines (RPH2; R = Cy, Ph) under mild conditions has been demonstrated using a zirconium complex, [kappa(5)-N,N,N,N,C-(Me3SiN-CH2CH2)(2)NCH2CH2NSiMe2CH]Zr (1). Exclusively anti-Markovnikov functionalized products were observed, and the catalysis is selective for either the secondary or tertiary phosphine (i.e., double hydrophosphination) products, depending on reaction conditions. The utility of the secondary phosphine products as substrates for further elaboration was demonstrated with a platinum-catalyzed asymmetric alkylation reaction.