Editing Theory of constraints (section)

===Marketing and sales===
While originally focused on manufacturing and logistics, TOC has expanded into [[sales management]] and [[marketing]]. Its role is explicitly acknowledged in the field of [[sales process engineering]].<ref name="Selden">{{cite book|title=Sales Process Engineering: A Personal Workshop |author = Paul H. Selden|publisher=ASQ Quality Press|location = Milwaukee, Wisconsin|year=1997|pages =33–35, 264–268|isbn=0-87389-418-9}}</ref> For effective sales management one can apply Drum Buffer Rope to the sales process similar to the way it is applied to operations (see Reengineering the Sales Process book reference below). This technique is appropriate when your constraint is in the sales process itself, or if you just want an effective sales management technique which includes the topics of funnel management and conversion rates.{{Citation needed|date=December 2007}}