In the period discussed in the article, the 18-19th century, the inventories of the Warsaw Royal Castle changed considerably. For a long time inventories were compiled for legal purposes: in connection with changes in the ownership or management of the Castle. These inventories did not list all the movables in the Castle, but only those considered most valuable. They recorded the state of affairs at a given moment and did not allow any supervision of movables within a longer period. The necessity of stricter property control finally led to changes in the form and content of Royal Castle inventories. Since the first decade of the 19th c. the inventories were compiled with the help of the architectonic plan of the Castle. On the basis of the plan rooms were given fixed numbers, which was to facilitate control over the movement of furniture and other accessories within the building. The next step was assigning inventory numbers to particular objects; this procedure was first applied in the inventory from 1837. But it was the year 1866 that saw a radical reform. It consisted in abandoning the 'topographic' type of inventory, which listed all the object located in each subsequent room, and adopting a functional classification of movables, based on materials of which they were made and purposes for which they were intended. Another innovation was the introduction of extended tabulation, allowing for the efficient control of the movement of the catalogued items in longer periods. Simultaneously, the range of objects included in the inventories was extending. From 1808 the records started to mention various previously omitted household utensils, e.g. glasses, bells, spittoons or chamber pots. The assortment increased systematically, to cover all the tiniest gadgets found in the Castle in the second half of the 19th c. The evolution of the inventories, conditioned by changes in the administration of the Castle, which were in turn connected with the current political situation, finally produced a modern format of inventory, suitable for efficient property management.