An archaeological watching brief carried out by the Colchester Archaeological Trust during the construction of an extension to the west of no 23 Endsleigh Court, Colchester. The work was necessitated by the construction of a new extension and associated services. <1> The foundation trenches were excavated using a tracked excavator equipped with either a 400mm or 600mm wide toothless bucket. As well as the foundation trenches, the excavation of a 1.2m deep pit for a soakaway was also monitored. The outer foundation trenches were dug to a depth of between 900mm and 1.1m below modern ground level. The internal beams were dug to a depth of c.700mm below modern ground level. There were no clear soil layers. However, the general soil profile was as follows: Layer 1 or L1 - 0-350mm – mid brown sandy-silt (topsoil). L2 - 350-600mm - lighter brown sandy-silt layer with frequent stones. L3 - 600-800mm - mottled sandy-silt. L4 - 800mm to the bottom of the trench – orange sand/gravel natural. The soil was undisturbed apart from a concrete slab which abutted the western wall of the house and was present to a depth of c 300mm below modern ground level. One undated ?pit was identified in the base of the foundation trench. Sherds of unstratified Late Iron Age-Roman pottery were recovered from the spoil heap and were retained by the landowner; it is unclear whether or the sherds came from the ?pit seen in the foundation trench. The site had not been heavily disturbed by modern building.