Individual, large-format architectural, engineering and other technical drawings and sketches showing plans, sections, elevations, details, schemes and diagrams of the National Theatre buildings, stage machinery and electrical and communication systems. In addition, there are some schedules and programmes that have been issued in large format on drawing sheets, and where they are available, numbered drawing lists. Occasionally paperwork such as drawing issue forms or letters are attached to a drawing, and where this is the case they have been catalogued together. Almost none of the drawings are the original ink and tracing paper versions. Instead they are printed copies, mostly diazotypes.
Theatre Projects Consultants Ltd produced a large number of such drawings but they also held many that were created by other consultants and contractors working on the National Theatre project, or who provided speculative drawings when applying for contracts - architects Denys Lasdun & Partners, structural engineers Flint & Neill Ltd, Evershed Power-Optics Ltd, Hall Stage Equipment Ltd, Tele-Stage Associates Ltd, Crown House Engineering Ltd, Rank Strand Electric Ltd, Varilectric Ltd, Waagner-Biro, P E Kemp Engineers Ltd, Gough & Co (Hanley) Ltd, J S Edwards (Engineers) Ltd, United Lift & Escalator Co Ltd, Loxton Engineering Services Ltd, Ainslie Controls Ltd, Metropolitan Tool & Products Ltd, W.H. Aubrey & Ptnrs, and the NT - and these are included in the series.
All companies who produced drawings had an internal referencing number scheme of letters and numbers by which they gave each drawing an individual identifier and grouped them together into, often thematic, series. If a drawing was reissued or revised, it would retain the same reference number but with the addition of an extra letter or number to indicate which issue it was. Reissues or revisions of a drawing, the dates they were made and the alterations that occurred are listed in the details section on each drawing, along with the company details, the title and the initials of those who drew and checked the drawings. There are a number of drawings and sketches that have their details box either partially filled in or not completed at all, meaning that they are undated and unreferenced.