The three-day methodology is actually used throughout Google internally (not Google Ventures which is a separate entity). I’ve been lucky enough to attend the Google Design Sprint Conference last year in San Francisco. There, the person who is in charge of the Google Sprint Academy, her name is Kai Haley. Her team published a three-day sprint because everyone is so busy. Day 1 focuses on understanding the problem and ideating solutions. Day Two is voting on one solution to prototype and completing the storyboard for the prototype in the morning and starting to build the prototype in the afternoon. The morning of Day Three is reserved for finishing the prototype and the afternoon is reserved for testing it with five people. When we test with five individuals, we get about 85 percent of the customer sentiment. You’ll learn a lot and have a clear direction on what to do next