It may not be scope creep that is troubling your project, but scope seep. And it may be self-inflicted. “Scope Seep” is what happens when the project team introduces additional scope of work not requested by the customer. Have a look at “If You Give a Mouse a Cookie”. It is not for children only. Quite the contrary.
“If You Give a Mouse a Cookie (If You Give…)”, by Laura Joffe Numeroff (Author) and Felicia Bond (Illustrator) ISBN-13: 978-0060245863.