Purchasing for the first time a large and expensive piece of equipment for the analytical laboratory can be a challenge. Even experienced laboratory managers can find buying a large piece of equipment quite daunting. Since the competition for funding for large expenditures is always keen, I hope by providing some guidance I can help ensure that your next purchase is successful. In starting the process to decide what should be purchased, it pays to have a clear expectation of what analytical job the equipment should do. It should also be clear who is going to be responsible for managing the purchase and also who will be responsible for operating and maintaining the equipment. Finally, for other than replacement equipment, it should be clear as to where it will be located and what services (electrical, ventilation, water, gases) are likely to be needed. Sometimes a laboratory needs to be rebuilt to accommodate a large item such as an NMR instrument or an inductively coupled plasma mass spectrometer. All of these questions need to be answered within the constraints of the budget available. In the routine analytical laboratory, the equipment or specification is usually quite clear, but for those who conduct research or develop analytical methods, there is often a desire for the equipment to do more than it is really capable of doing. Without a clear understanding of what the equipment will be used for, there is a good probability it will either not meet expectations or be overloaded with accessories that will not be used. Possibly an essential option will be missed because its usefulness was not considered. For example, it is tempting to add tandem mass spectrometry capability to a high-resolution mass spectrometer so that analytical capability is increased; however, unless this will be used as a research tool, the additional capability is unlikely to be used in a routine trace organic laboratory. At this stage of the process, it is worthwhile discussing with sales staff from all of the likely suppliers your possible purchase. Often they can be very helpful in providing information on the capability of the instrument, possible applications, appropriate configurations and options and may even provide a list of satisfied customers. Sometimes, if purchasing a less common type of equipment, it may be worthwhile having the analyst visit a laboratory where one is operating. During such a visit, it is possible to see how the equipment actually performs, its limitations and obtain some idea of down time and maintenance costs. We did this before buying an automatic weighing instrument and on the knowledge gained drew up a specification to purchase one. Since modern instruments are very dependent on computers to control them, a visit or demonstration is a good way to assess the appropriateness of the control and reporting software. Experience indicates that for many suppliers this is the weakest link in their product as sometimes the software does not actually do what it should. Often a new model or type of equipment is not really usable until an upgrade correcting the faults is available. The computers supplied are sometimes barely adequate for the task in terms of on-board processing capability and disc storage. Sometimes, performance can be improved by upgrading both before purchase as this is usually cheaper than upgrading later. The issue of the software licences should be considered as companies have different licences: some allow use on other computers for data processing; others require the purchase of a second licence for this purpose. Upgrading the printer from an inkjet type to a laser type can improve productivity and save cost in the long term. Once the specification has been decided on, the question arises as to who will supply the instrument and at what price. Many organizations such as government laboratories, large corporations and universities will insist that a competitive tendering process be used. This is to ensure Anal Bioanal Chem (2009) 393:13–14 DOI 10.1007/s00216-008-2392-2