In consumer packaged goods (CPG), understanding how consumers shop is a necessity. Brands are competing not just on product quality or price, but on their ability to be in the right place, at the right time, with the right message. To succeed, both CPG manufacturers and retailers must rely on tools that decode consumer behavior. Two of the most powerful tools in this space are Purchase Structures and Consumer Decision Trees (CDTs).

While each offers a unique lens into the shopper journey, it’s their combined use, and the collaboration between CPGs and retailers around them, that unlocks true category growth.

What Are Purchase Structures?

Purchase Structures are based on actual purchase behavior: what consumers buy and how they substitute products. These structures are typically derived from panel data, loyalty card data or basket analysis. They help identify which products consumers see as interchangeable, providing a map of how shoppers group brands, formats, sizes and tiers in their minds, based on real-world decisions.

In CPG, Purchase Structures are instrumental in:

Optimizing shelf layouts and planograms.
Identifying gaps and overlaps in assortment.
Guiding innovation grounded in shopper needs.
Improving retail execution by aligning with true shopping behavior.

For example, if data shows that shoppers frequently substitute between two yogurt brands, but rarely switch between cup and drinkable formats, that insight helps inform how products should be grouped on the shelf.

What Are Consumer Decision Trees (CDTs)?

Where Purchase Structures capture behavior, Consumer Decision Trees (CDTs) focus on decision-making logic: how shoppers consciously evaluate options. CDTs are typically built using survey data, where consumers indicate the order in which they consider product attributes: Do they choose based on format first (e.g., granola bar vs. protein bar) or by brand, flavor or price?

In CPG, CDTs help answer key questions like:

How should we prioritize product claims or attributes in messaging?
What attributes drive choice online vs. in-store?
How should filters be structured on the digital shelf?

For example, a CDT might reveal that pet food shoppers first choose based on pet type, then format (wet vs. dry), followed by brand and finally price. That insight informs how to structure category pages on a retailer’s website or which benefits to lead within packaging and advertising.

Different Tools for Different Questions

While Purchase Structures and CDTs are both used to understand consumer behavior, they serve very different purposes:

Tool	Data	Answers	Used For
Purchase Structure	Scanner/POS data, loyalty data, basket analysis, switching matrices.	Reflects behavioral outcome — what they actually do and buy.	Assortment, shelving, innovation.
Consumer Decision Tree (CDT)	Panel data, shopper interviews, decision mapping.	Reflects mental process. How shoppers consciously navigate options.	Messaging, pack architecture, digital experience.

When used together, these tools offer a complete understanding of both the what and the why behind shopper behavior.

Think of it this way:

CDT = Shopper’s logic → “I want a cola → I prefer Brand A→ I’ll get the 1.5L bottle.”
Purchase Structure = Shopper’s behavior → “When Brand A 1.5L is out of stock or not on promo, I switch to Brand B 1.5L or buy two cans.”

A Retailer’s Perspective

From a retailer’s perspective, these tools are just as valuable. Purchase Structures enable retailers to create more intuitive and efficient shelf layouts by reflecting how consumers naturally shop the category. This leads to improved shopability, faster navigation and ultimately increased conversion and basket size.

CDTs, meanwhile, help retailers design a clearer shopper journey — whether through shelf signage, navigation menus on e-commerce sites or filter hierarchies in mobile apps. Understanding the sequence of decision-making allows retailers to remove friction points and influence shopper decisions at the right moment.

Retailers also benefit when CPG partners bring both tools into joint business planning discussions. With shared shopper insights, teams can align on shelf space, pricing tiers and promotional strategies that support the entire category, not just individual brands.

CPG and Retailer Collaboration: Building Shopper-Centric Strategy

Successful CPG-retailer collaboration around CDTs and Purchase Structures starts with shared goals: improve the shopper experience, grow the category and create value for both sides.

Here's how this collaboration typically unfolds:

1. Data Collection & Insight Sharing
CPGs often lead the way in developing these tools by leveraging rich data sources: loyalty data, consumer surveys and behavioral analytics. Retailers contribute valuable contextual insights, such as in-store conditions, channel-specific nuances or shopper feedback from frontline employees.

2. Joint Interpretation & Activation
With insights in hand, both parties work together to activate the learnings. For example:

Use Purchase Structures to rationalize assortment and reduce duplication.
Use CDTs to inform packaging redesigns or determine which claims to feature in an ad campaign.
Use both tools to redesign a category aisle or restructure an e-commerce category page.

3. Test and Learn
Both retailers and manufacturers benefit from piloting changes, such as a new shelf layout, product placement strategy or digital content refresh, and using metrics like conversion rate, sales lift and shopper satisfaction to refine the approach.

Real-World Example: Category Reset in the Snacks Aisle

Consider a joint project between a snack brand and a major retailer. The brand’s Purchase Structure analysis revealed that consumers viewed “better-for-you” snacks as distinct from traditional indulgent snacks, even if they shared formats (e.g., chips, bars). Meanwhile, the CDT showed that shoppers first chose by snack type, then health benefit, then brand.

Armed with these insights, the retailer reorganized the snack aisle to separate functional and indulgent segments more clearly. The brand adjusted its packaging to lead with “protein” benefits more prominently and aligned digital ad copy to match decision flow.

The result? Improved navigation, stronger brand recall and a lift in category sales.

The Competitive Advantage of Shopper-Centric Strategy

In an industry where shelf space is finite and digital attention spans are short, understanding how consumers think and behave gives CPG brands and retailers a competitive edge.

CPGs can build products and messaging that align with how shoppers choose.
Retailers can design store experiences that match real-world behavior.
Together, they can deliver a more relevant, seamless and satisfying shopper journey.

By integrating Purchase Structures and CDTs into shared planning, CPGs and retailers go beyond pushing products. Instead, they co-create category experiences that win with the shopper.