Automatic fluid sampling and monitoring apparatus provided as a unitary structure (1, 2), and capable of collecting samples at selected intervals, monitoring the level of a condition of the fluid at selected intervals, and collecting (20) and storing sampling and fluid condition data for later retrieval. Sampling operations may be controlled on the basis of time and/or levels of condition being monitored (20). Where the apparatus also incorporates an internal flow measuring assembly, or is connected with an external flow meter, sampling operations may also be controlled on the basis of flow rate. The apparatus includes a self-contained microprocessor control section (15) for automatically controlling sampling operations, calculating fluid condition levels on the basis of signals from a sensor, and storing data relating to sample collection and the condition. Stored data can be called up on a display (18) of the apparatus, or transferred (16) via a portable transfer unit to an external output device, such as a printer, for producing a hard copy of the data.