Almost every day in the news I read about another celebrity entering rehab, writes Clea Myers. 

Or re-entering. Or leaving early. Pete Docherty, Amy Winehouse, Kerry Katona, Keith Urban, Britney Spears, Kirsten Dunst and Whitney Huston, to mention a few of the best known.

Often reporters highlight the superficial aspects of these treatment centres, as if they are describing a luxury spa. While there are disparities between levels of comfort within facilities, one unifying feature defines their existence: concentrated treatment for addictive illness.