Glenn Croston, author of 75 Green Businesses and Starting Up Green. Croston, whose interest in green businesses started simply with hopes of creating a better world for his children and future generations, is here to say that it is not very hard to start up a green business. Glenn Croston, author of 75 Green Businesses and Starting Up Green. Croston, whose interest in green businesses started simply with hopes of creating a better world for his children and future generations, is here to say that it is not very hard to start up a green business.