Purlem goes international with this personalized URL (PURL) case study.
A Fitness Club in Finland used Purlem to track the responses of their marketing campaign to old gym members. (Members that were once members, but have let their membership expire). The goal of their campaign was to simply reach out to these members and offer them other membership options that would fit their lifestyle.
A postcard was mailed out to these members with a PURL on it. The PURL would direct them to a website like seen below.
Traditinally a postcard would get a 1-3% response rate. But when they used the PURLs, they had a 22.3% response! Below is a chart of the responses for this campaign over time: