In this talk, I will present an overview of recommender systems, including traditional content based and collaborative filtering. I will also touch upon some current trends and breakthroughs in this area. I will then provide an overview of how we develop recommendations here at Etsy. Specifically, I will provide an overview of our journey from linear ranking models to a non- linear deep neural network ranking model, the challenges we faced and the lessons we learnt. I also plan to present our work on a novel custom objective function to build a recommendation model that jointly optimizes both relevance and profit.