---
id: "prereq-geofencing-basics"
type: "prereq"
source_timestamps: ["¶2"]
tags: ["ad-tech-fundamentals"]
related: ["concept-absolute-proximity"]
reason: "Understanding the baseline strategy (drawing a circle around a store) is necessary to grasp why the authors' multi-dimensional strategy is a significant evolution."
sources: ["tail1"]
sourceVaultSlug: "hbr-seg-tail1"
originDay: 1
articleStem: "hbr-tail-115-location-based-advertising"
sourceUrl: "https://hbr.org/2026/03/a-better-strategy-for-location-based-advertising"
sourceTitle: "A Better Strategy for Location-Based Advertising"
---
# Basic Geofencing and Radius Targeting

**Why it's a prerequisite:** Understanding the baseline strategy — drawing a circle around a store — is necessary to grasp why the authors' proposed multi-dimensional strategy is a significant evolution.

**What you need to know:** How standard location-based advertising works today — specifically, the practice of setting a pin on a map and **drawing a radius (e.g., 5 miles)** within an ad platform to serve ads to devices inside that boundary. This baseline is the subject of [[concept-absolute-proximity]] and the thing the whole source argues against.