Vinylphosphine−borane complexes are easily synthesized by regio- and stereoselective hydrophosphination of terminal alkynes with use of secondary phosphine−boranes as hydrophosphinatingagent. The regioselectivity of the reaction is efficiently controlled by the choice of the activationprocess: thermal or metal catalyst activation. The vinylphosphine derivatives are purified bychromatography on silica gel. Scalability of the process is demonstrated on a gram scale. This simpleroute should promote the use of vinylphosphines as building blocks for organic and organometallicchemistry.