In the upcoming chapter, we will review the clinical insights that led to the formation of the currently used ovarian stimulation protocols. We will also explore key protocols for controlled ovarian hyperstimulation, spanning from the early stages of assisted reproductive technologies (ART) to the present day. Initially, we will delve into the endeavors aimed at increasing oocyte yield by developing and orchestrating ovarian stimulation agents. Subsequently, we will examine the evolution of standard short and long gonadotropin-releasing hormone (GnRH) agonist and antagonist protocols and the specialized protocols tailored for patients with polycystic ovary syndrome (PCOS) and poor responders. We will conclude with an endeavor to glimpse into the future, contemplating where the evolution of IVF may lead.