This presentation offers a short history of the Expert Committee. It explains some of the equipment which we use and shows the extensive reference collections available to us, including the privilege of access to the collection of the society's Patron, Her Majesty The Queen, in order to make comparisons. However, much of the presentation will focus on some of our past patients and the sort of conundrums that these produce for expertisers. Almost by definition, expert opinions tend to be sought for more challenging and difficult items. Although many of these can be relatively straightforward with knowledge, the right equipment, and reference material, others can be very difficult.