Embodiments of the present invention provide an approach for broker facilitated, publisher peer-to-peer (P2P) collaboration in a publish-subscription (pub/sub) environment. Specifically, in a typical embodiment, a broker system acts as an intermediary between publisher systems and subscriber systems in the pub/sub environment. Along these lines, the broker creates an administrative communication channel between known publisher systems and the broker system. Using this administrative communication channel, the broker system informs individual publisher systems about other publisher systems such that peer-to-peer communication channels between two or more publisher systems can be established. This can be accomplished using the broker system's knowledge of data being published by the individual publisher systems. Regardless, the publisher systems can then use information received from the broker system to: establish a P2P communication channel with one or more other publishers; identify a set of data that has commonality to the peers (and thus has a potential to be cached); and negotiate a caching schema/approach to store the data in a cache. The broker system may generate a set of cache key/unique identifiers and communicate the unique identifiers to at least one of the publisher peers, which will then share the unique identifiers among the peers. The set of data will then be cached (e.g., by a publisher system, a broker system and/or a subscriber system) using the unique identifiers.