Every marketing organization wants to know the return on investment (ROI) of their marketing campaigns. Ideally, the cost of the marketing campaign should be less than the amount of revenue generated by it. For enterprises with long sales cycles and many online/offline marketing campaigns, it is hard to analyze the linkages between marketing campaigns run many months ago to revenue won today. This talk will explore how machine learning powered approaches can help B2B marketers optimize spend across all their marketing channels.