---
title: Relation Fields
description: Connect records across different objects using relation fields.
---

## Types of Relations

### One-to-Many
One record in Object A can be linked to many records in Object B.

**Example:** One Company can have many People (employees).

### Many-to-One
Many records in Object A can be linked to one record in Object B.

**Example:** Many People can belong to one Company.

### Relations to Multiple Object Types

Some objects can link to multiple object types on one side of the relation.

**Example:** A Note can be attached to one Person AND one Company AND one Opportunity simultaneously. The Note is on the "many" side, connecting to multiple "one" sides.

<img src="/images/user-guide/fields/many-to-one-morph.png" style={{width:'100%'}}/>

Similarly, a Project (on the "one" side) could receive links from multiple People, multiple Companies, and multiple Notes.

<img src="/images/user-guide/fields/one-to-many-morph.png" style={{width:'100%'}}/>

<Warning>
**Import/Export limitation**: Relations pointing to multiple object types are not yet supported for CSV import/export. This is on our roadmap.
</Warning>

### Many-to-Many

Many records in Object A can be linked to many records in Object B.

**Example:** Many People can be linked to many Projects, and vice versa.

Many-to-many relations use a **junction object** pattern: an intermediate object that connects both sides. With the junction relation feature, Twenty displays the final linked records directly, hiding the intermediate object from the UI.

<img src="/images/user-guide/fields/junction-relation-diagram.png" style={{width:'100%'}}/>

<Warning>
**Lab Feature**: Junction relations must be enabled at **Settings → Updates → Lab** before use.
</Warning>

See [How to Create Many-to-Many Relations](/user-guide/data-model/how-tos/create-many-to-many-relations) for a complete step-by-step guide.

## Creating a Relation Field

1. Go to **Settings → Data Model**
2. Select the object where you want to add the relation
3. Click **+ Add Field**
4. Select **Relation** as the field type
5. Choose the target object(s) to relate to
6. Configure the relation settings:
   - **Field name on source object**: The name of the relation field on the object you're editing
   - **Field name on destination object**: The name of the relation field that will appear on the target object
   - Relation type (one-to-many, many-to-one)
7. Click **Save**

## Standard Relations

Twenty comes with pre-built relations between standard objects:

| From Object | To Object | Relation Type |
|-------------|-----------|---------------|
| People | Companies | Many-to-One |
| Opportunities | Companies | Many-to-One |
| Opportunities | People  | Many-to-One |

## Best Practices

### Planning Relations
- **Map your data model**: Plan relations before creating them
- **Consider direction**: Think about which object "owns" the relationship
- **Avoid circular dependencies**: Keep your data model clean

### Naming Relations
- **Use clear names**: Make it obvious what the relation represents
- **Be consistent**: Use similar naming patterns across relations
- **Consider both sides**: Name both sides of the relation appropriately

### Performance
- **Don't over-relate**: Too many relations can slow down your workspace

## Limitations
- **Deleting relations** removes the link but not the related records
- **Circular relations** should be avoided for data integrity