Data pooling comes up routinely in drug or device trials. Sometimes questions of whether pooling is appropriate arise, and such questions can be referred to as those of poolability. As a result of the generality of the term, poolability comprises a heterogeneous set of problems that need to be addressed on a case by case basis, depending, among other things, on whether the groups in question are investigational sites, geographical regions, clinical studies (or substudies), patient populations, device models, and so on. The participants are expected to share their experiences on this issue.