Set something in train
Definition 1 of 1
Pro Tip 1/3Causative Implication
The phrase suggests someone initiates a process that continues without their direct involvement. 
The CEO’s decision set changes in train that would reshape the company.
Pro Tip 2/3Not Instantaneous
Indicates a process that doesn't happen immediately but unfolds over time. 
Building the new library set plans in train for a community learning hub.
Pro Tip 3/3Neutral Tone
The phrase is neutral and can be used in both positive and negative contexts. 
The new policy set in train a debate about privacy rights.