Abstract: A planning assistance system according to an aspect of the present disclosure includes at least one memory configured to store instructions; and at least one processor configured to execute the instructions to: receive a comment of each of users for each of a plurality of events included in a travel plan; and cause a display to display the received comment in association with each of the events.

Abstract: A sales promotion support device according to the present disclosure includes: one or more memories storing instructions; and one or more processors configured to execute the instructions to: acquire at least one of behavior information that is information regarding a behavior of a user and a time at which a sales promotion plan is to be provided; estimate an acceptability of the user to a sales promotion plan based on the at least one of the behavior information and the time; and determine a sales promotion plan to be provided to the user according to the acceptability.