The first edition, published in 2001, reviewed the multiple facets of the cosmetic field
including the physiology of cosmetics targets and the safety, legal and regulatory context worldwide. It gave a broad overview of cosmetic ingredients, vehicles and finished products, and described the main methodologies used for microbiology, safety and efficacy testing. In the second edition (2006), we examined the future of cosmetology by the addition of chapters related to new ingredients, new delivery systems and new testing methodologies, but also by asking the previous authors to update their chapter with their speculation about the future in their field of expertise. To make the information more accessible, chapters were significantly reorganized.