# Product Family

**URL:** https://kaizumi.com/dictionary/product-family

**Description:** A product family is a group of products that share similar processing steps and equipment, enabling flow cell design and value stream focus.

**Category:** lean-tools

**Tags:** flow, foundational

## Definition

A product family is a group of products that pass through similar processing steps and common equipment, making them suitable for a dedicated flow cell or value stream. Identifying product families is a crucial early step in lean transformation: products grouped into families can share a cell, a scheduling system, and a value-stream focus. The grouping criterion is process similarity (do they use the same operations in roughly the same sequence?), not customer segments or marketing categories. A product family matrix helps visualize which products share which processes.

## Examples

### Manufacturing

> A fastener manufacturer analyzed 200 products. Three product families emerged based on process similarity: (1) cold-headed bolts, (2) machined screws, (3) formed brackets. Each family could have a dedicated cell with its unique equipment sequence, even though all three served the same automotive customers.

### Healthcare

> A laboratory grouped tests into families based on processing equipment: (1) chemistry analyzer tests, (2) immunology tests, (3) hematology tests. Each family followed a different equipment path, enabling focused flow improvement for each.

### Service

> An insurance company identified product families by processing requirements: (1) auto claims, (2) property claims, (3) liability claims. Each required different expertise, systems, and processing steps—different product families despite all being "insurance claims."

## Key Points

- Grouping based on process similarity, not market categories
- Enables dedicated cells, focused scheduling, and value-stream management
- Products in a family should share 60-80% of processing steps
- Product family analysis precedes cell design and value-stream mapping

## Common Misconceptions

**Product families are defined by customers.** A customer might buy products from multiple families. Families are defined by process similarity, not customer relationship.

**All products must fit into families.** Some products are "orphans" that don't fit cleanly into any family. These may require separate handling or assignment to the closest family.

## Try It

A value stream map covers one product family, never a whole operation. Once you have grouped items by process similarity, map the family you chose. The builder below lays out process steps, the inventory sitting between them, and the information flow that schedules each one, then sums lead time against processing time. If the grouping is right, every item in the family fits the same map. (Also available as a [standalone tool](/tools/vsm).)

<!--TOOL:vsm-->

## See Also

- [Product Family Matrix](/dictionary/product-family-matrix) - Tool for identifying families
- [Cellular Manufacturing](/dictionary/cellular-manufacturing) - Where product families are built

Source: https://kaizumi.com/dictionary/product-family
Licence: free to quote and cite with attribution to Kaizumi.