The Karen M. Lewis Collection of KLM Houses is a small collection consisting of information related to small ceramic Delft houses given away by KLM airlines to first class and business class passengers in the 2010s. The collection includes a brochure from KLM describing and illustrating the collectible houses; a checklist card; four cards describing real buildings on which some of the ceramic houses are based; and some magazine clippings about the collectible houses.