We'll introduce the Microsoft open source, production-grade deep learning Cognitive Toolkit (formerly CNTK) in a talk that will be a prelude to a detailed hands-on tutorial. The Cognitive Toolkit was used recently to achieve a major breakthrough in speech recognition by reaching human parity in conversational speech. The toolkit has been powering use cases leveraging highly performant GPU platforms. It is being used by several customers both on-premises and on Azure cloud. We'll introduce different use cases leveraging fully connected CNN, RNN/LSTM, auto encoders, and reinforcement learning. We'll deep dive into topics that enable superior performance of the toolkit in comparison with similar open source toolkits. We'll showcase scalability across multiple GPUs and multiple servers. We'll provide a teaser hands-on experience with Jupyter notebooks running on Azure with simple introductory to very advanced end-to-end use cases.