Dámaso started to practice at the law firm Uría Menéndez. Initially he specialised in mergers and acquisitions. Together with this, he worked as corporate governance and company law counsel for Spanish listed companies. Later on he moved to the litigation department and he participated in various judicial and arbitration proceedings. In 2008 the Rafael del Pino Foundation granted him a scholarship to pursue an LL.M specialised in Corporate and Commercial Law at London School of Economics.
He is a partner at the law firm Arias SLP and Ph.D candidate at the Universidad Autónoma de Madrid.