1. A method for privacy-preserving sharing of data for secure collaboration, comprising: obtaining a first set of data associated with one or more entities; negotiating, with a potential partner, to determine a metric for deciding whether to share data, wherein the potential partner is associated with a second set of data; computing a value for the metric in a privacy-preserving way, based on the first set of data and the second set of data; determining whether the metric value exceeds a predetermined threshold; and responsive to determining that the metric value exceeds the predetermined threshold, sharing the first set of data with the potential partner, while controlling how the first set of data or subsets of the first set of data should be shared to optimize benefits and risks of collaboration.