If you’re a digital marketing professional, you’ve likely woken up from a dream where you just saw every interaction a site visitor or customer had with your brand tracked perfectly from start to finish. Oh, is that just what I dream about? Luckily, there are solutions. Unluckily, they can be tricky.

For most, last-touch attribution is the most realistic measurement model, thanks to its affordability and simplicity to implement. Last-touch attribution works, but it doesn’t tell the whole story. Typically, lower-funnel tactics like paid search will show as main conversion drivers in a report using last-touch modeling. What that report can’t account for is the many touchpoints a user could have engaged with before that final conversion. This is important because making decisions based on results in these reports could lead to a less-than-optimal media plan.

Multi-touch attribution is the more holistic solution. It assigns fractional credit to each touchpoint along the path to conversion. The result is a meaningful data model that allows marketers to make informed decisions and ensure all important channels are represented accurately in their media plans.

Is multi-touch attribution really the dream solution? Besides the work needed to implement tracking successfully across all touchpoints, and the cost typically associated with this “behind the scenes” work, multi-touch attribution requires jumping one major hurdle. A successful model connects touchpoints and assigns credit by joining data sets from each touchpoint based on a unique (and anonymous) identifier. This allows the model to see a user’s journey from start to finish. However, lots of savvy consumers are moving from one device to another, and blocking cookies from their browsers and apps. Some also feel reluctant to share any personal information online as they hear stories about larger companies using data they collect in ways these users don’t understand or approve of. These factors combine to make it so some of those unique identifiers aren’t present to connect touchpoints, and the model has holes.

Both last-touch and multi-touch attribution have limitations. Using one of these models is still the best option for most marketers. Being data-focused and remembering these limitations when making any media decisions will keep attribution from becoming the monster under your bed.