This paper divides the assessment up into anatomical (nasal and oropharyngeal), endoscopic and imaging. It points out the salient features to look out for in OSA patients with regards the nasal valve and also oropharyngeal anatomy, with tonsil hypertrophy grading being indicative of OSA (type IV). Mallampati classification is described with useful colour images and the Friedman scoring system is explained as a combination of palate-tongue position, tonsil size and body mass index (BMI), to gauge predictors of success of uvulopalatopharyngoplasty (UPPP.) Both the Fujita and Moore classification systems describe the level of obstruction. Interestingly, the authors debate the use of Muller’s manoeuvre, citing the surrounding conflicting literature regarding its use in predicting the level of obstruction and hence the success of UPPP. They also describe the use of CT or MRI in the context of obstruction level, evaluating the cross sectional areas of the nasopharynx and oropharynx. Interestingly, despite acknowledging the radiation dose of a 3D cone beam CT, it appears to be commonplace within this particular sleep centre in Mississippi, USA. Pharyngometry and critical closing pressure is also described by the authors as a simple and effective way of determining OSA, although it is still to be combined with other data such as neck circumference and BMI to predict OSA severity and surgical response. Sleep endoscopy is left to the following article but one seems a little unclear overall as to which assessments and investigations they favour as a sleep centre. Perhaps an example of a patient journey through their clinic may have been more illustrative and useful to those setting up services with an interest in assessing these patients.