The diagnosis of intra-abdominal hypertension (IAH) or abdominal compartment syndrome (ACS) is heavily dependent on the reproducibility of the intra-abdominal pressure (IAP) measurement technique. Recent studies have shown that a clinical estimation of IAP by abdominal girth or by examiner's feel of the tenseness of the abdomen is far from accurate, with a sensitivity of around 40%. Consequently, the IAP needs to be measured with a more accurate, reproducible and reliable tool. The role of the intra-vesical pressure (IVP) as the gold standard for IAP has become a matter of debate. This review will focus on the previously described indirect IAP measurement techniques and will suggest new revised methods of IVP measurement less prone to error. Cost-effective manometry screening techniques will be discussed, as well as some options for the future with microchip transducers.