Chapter 15 499 of formulations, while also providing recommendations for performing these tests in an optimal manner. Again, the ability to quantify the magnitude of a performance benefit has become very popular in recent years, in large part due to the popularity of quantitative claims. As a result, the scientific literature is filling with new approaches and methods that attempt to quantify different properties, or allow for benefits of even greater magnitude to be realized. Without wishing to stifle this process, it is often desirable to support claims using conventional, well-regarded measurement techniques that are established and recognized within the industry. Moreover, approaches that best simulate actual usage are obviously preferred. Standard testing protocols are, to all intent and purpose, absent from the hair care industry however, there are a number of methods and approaches that have become widely adopted throughout the industry (although each laboratory likely performs them in their own slightly different manner), and hereforth this chapter now focuses on these techniques and their use in substantiating hair product claims. Quantifying Surface Lubrication via Instrumental Combing Experiments A number of methods can be/have been conceived to measure lubrication of hair by conditioning treatments. However, approaches that better simulate consumer habits and practices obviously have more relevance and are of a greater value. As such, by far the most popular methodology involves instrumental combing (or brushing) experiments. It has now been more than 35 years since Garcia and Diaz published their seminal paper on how to perform instrumental combing experiments on hair 1 and since this time, it is difficult to think of a more heavily cited reference in the hair care field. The attraction of the method lies with its obvious practical applicability. The approach involves the use of a mechanical testing device (e.g. an Instron, Diastron, or Texture Analyzer) which measures the friction generated upon pulling a hair tress through a brush or comb. Therefore, lubrication is evaluated in terms of a decrease