Blockchain is a verifiable distributed ledger that can be used for a variety of applications like financial transactions, smart properties, credential management, internet-of-things, supply chain management and even decentralizied autonomous organizations (DAO). The popularity of Bitcoin has resulted in creation of alternate cryptocurrencies based on Blockchain technology. Smart contracts on blockchain is believed to be a disruptive technology. There has been a hype about blockchain technology, cryptocurrency and contracts and governments and industries have shown great interest in developing and deploying this technology. Is the hype justified? What can and cannot be done efficiently using blockchain? What applications can be put on blockchain? How to design a scalable, robust, secure blockchain? How vulnerable are current designs and how can they be mitigated? What are the cryptographic issues that need be addressed? 

The workshop aims at finding answers to the above questions and much more. The workshop will bring researchers and practitioners to discuss current blockchain technology, underlying theoretical foundations, and applications. BCC'17 will discuss and analyze current cryptographic protocols underlying blockchains, and cryptocurrencies and propose new ways to design secure, robust, scalable blockchains. The workshop welcomes academia, government, industry, and contributing individuals to submit unpublished, original papers in theoretical and practical aspects of blockchain technologies, cryptocurrencies and smart contracts.