First ACM Workshop on Information Sharing and Collaborative Security Sharing of security related information is believed to greatly enhance the ability of organizations to defend themselves against sophisticated attacks. If one organization detects a breach the automated sharing of observed security indicators (such as IP addresses, domain names etc.) provide valuable, actionable information to others. Through analyzing shared data it seems possible to get much better insights into emerging attacks. Sharing higher level intelligence about campaigns, threat actors and mitigations is also of great interest. Both in the US and the EU there are major efforts underway to strengthen information sharing. Yet there are a number of technical and policy challenges to realizing this vision. Which information exactly should be shared? How can privacy and confidentiality be protected? How can we create high-fidelity intelligence from shared data without getting overwhelmed by false positives? The first Workshop on Information Sharing and Collaborative Security (WISCS 2014) aims to bring together experts and practitioners from academia, industry and government to present innovative research, case studies, and legal and policy issues. The workshop solicits original research papers in these areas. Workshop proceedings will be published in the ACM Digital Library. Topics of interest for the workshop include, but are not limited to: * Collaborative intrusion detection * Case studies for information sharing * Domain name and IP address blacklisting * Collaborative approaches to spear-phishing and DDoS attacks * Data deidentification * Privacy and confidentiality * Cryptographic protocols for collaborative security * Scalability of security analysis on shared data * Ontologies and standards for sharing security data * Human factors in collaboration * Policy and legal issues * Surveillance issues * Trust models * Attacks on information sharing * Economics of security collaboration See: https://sites.google.com/site/wiscs2014/ for further details.