Most Internet users consume video in some form or another. However, despite the huge amount of content available on various video sites, typical interactions with the videos are limited to posting and viewing. Overall, online video artifacts are still treated as a simple finished product for individual passive consumption with limited interaction techniques. Video as a medium has huge potential to be used for communication and collaboration but people still mainly use multiple separate tools such as YouTube combined with email for their video-centered collaboration tasks. A tool that can support collaboration among group members while working around videos will need specific design affordances and novel interaction techniques. However, research in video interaction techniques has mainly focused on improving interaction with video for passive consumption and not for active group collaboration.In this dissertation, I have studied the current state of video-centered collaboration and have surveyed features and problems of various video-centered collaboration tools. I have employed a `research through design' approach of ideation, design and critique to develop a new video-centered collaboration system called the Video Collaboratory with various novel interaction techniques. The Video Collaboratory includes techniques such as integrated annotations in multiple modalities, a segment selector, contextual navigation, color-coding for group members and video looping in slow motion. These novel techniques allow users to navigate, select, mark and annotate specific segments of a video using multiple modalities that makes the collaboration efficient, immersive and powerful. I have evaluated the Video Collaboratory through formative and summative studies and in this thesis I elaborate on these results.The Video Collaboratory has proven to be instrumental in collaborating around video when working in a group. Based on the results of my studies and experiments, I have presented a set of guidelines for designing affordances for video-centered asynchronous collaboration tools and I have discussed some future research avenues.