After 25 years prescribing non surgical rejuvenation and reviewing many product ranges...I can safely say without contradiction.
 "No other combination of home skin care products can match the ‘wow’ effect that my patients receive with ObagNu-Derm System."
Peter Dixon Plastic Surgeon

Over the years patients  tried other products or mixed and matched! After a short time they return to Obagi Nu-Derm system. .
The return of natural skin translucency is the hallmark of a patient who maintain skin health with the NU-Derm transformation course!

Obagi Nu-Derm is a 3 to 4 month home treatment course of powerful skin lighteners, exfoliators enhanced by Obagi Patented Therepeutics™  penetration technology!. 

Because the products work sequentially, it is recommended for best result, patients stop using any other skin care products and use only the complete Nu Derm system suitable for their skin

The exfoliators and penetrators allow the skin enhancers  & lighteners to reach down deep into the skin to treat the really stubborn pigment.
In my practice,  patients use Obagi for a total of 3 or 4 months . After the initial course I recommended a maintenance program specific to their skin.

Additionally 2-3 times per year I recommended a 3-4 week shock stimulation program to ensure optimum skin health is maintained and reducing the requirement for deeper peels & or lasers .

Q&A - Obagi Nu-Derm