Filter technology seems relatively stable, although absorbable devices are an area of investigational interest. The indications for filter placement remain controversial, with wide variations in adherence to guidelines, and relatively poor quality of data about the specific prophylactic indications of trauma or bariatric surgery. The outcomes of filters are not well-defined despite widespread clinical use, and good data remains difficult to obtain. Several larger database and institutional retrospective studies support the notions that while filters prevent pulmonary embolism, they may be associated with venous thrombotic complications. Some subsets of cancer patients may be at increased risk of these complications, but whether the filter or the underlying hypercoagulable state is the cause is not clear. Lastly, although the benefits of filter retrieval are widely assumed (but not proven), filter retrieval rates remain lower than expected. The single most influential factor in improving filter retrieval rates is dedicated follow-up with intent to retrieve the filter.