The Order Books record the details of the workings of Soane's architectural office on a daily basis. They are the earliest such records to survive from a practice which was set up in 1780 and which took on articled pupils from 1784. Whilst labelled 'Order Book' externally, internally the two surviving Order Books have inscribed on pages 2 and 3 'The Day Book for the year 1787', linking them to the subsequent series of records known as the Day Books (q.v.).

In 1787, Soane's practice was operating from his house at 77 Welbeck Street, to which he had moved in November 1784, though we have no details of how he accommodated his office within this property.

Each day has a double-page spread with information recorded in four columns, labelled at the start of the volume: 'Messages left &c', 'Business to be done & Materials wanted', 'Drawings sent, Bills &c paid and Money rec[eive]d' and 'Neill, Sanders & Donnell Time' [John Sanders and John McDonnell articled pupils and Thomas Neill, Clerk].

Entries relating to money are lightly crossed through in ink, indicating that those transactions have been recorded in the relevant Account Journal - a process that took place periodically. 'Ent[ere]d' on the front board presumably indicates that all financial transactions have been so recorded.

The fourth column records, under the name of the client, what each pupil was working on each day, to enable the clients' bills to be made out at the end of a job.

A printed label affixed to the inside of the front board records 'This is the property of Sir John Soane's Museum' and is signed by Arthur Bolton, Curator 1917-45.

The two volumes are bound in parchment and inscribed in black ink on the spine and front board.