# Custom Fields
Custom fields let you track data that is unique to your workflow - beyond the built-in contact fields. Each book has its own set of custom field definitions, and every contact in the book can have a value for each field.
> [!quote] Your Data, Your Way
> Not every CRM fits every workflow. Custom fields let you ==shape RelayBook around your process==, not the other way around.
## Field Types
When creating a custom field, choose one of four types:
| Type | Description | Example |
|------|-------------|---------|
| **Text** | Any free-form text value | Account number, referral source |
| **Number** | Numeric values | Lead score, revenue, headcount |
| **Select** | A fixed list of options | Plan tier, status, region |
| **Date** | A calendar date | Contract renewal, last meeting |
## Creating a Custom Field
Custom fields are managed from the **Book Settings** panel:
1. Open the book and go to **Settings**
2. Find the **Custom Fields** section
3. Click **Add field**
4. Enter a name, choose a type, and save
For select-type fields, add your initial options when creating the field. You can always add more later.
## Editing Select Options
You can add or remove options on a select-type custom field at any time:
1. Open **Edit Contact** for any contact in the book
2. Find the select field and click the **options toggle** (shows current option count)
3. Type a new option and press Enter or click **Add**
4. Click **x** next to an option to remove it
> [!note]
> Removing a select option does not clear it from contacts that already have that value - their existing value is preserved as-is. To clean up, update those contacts manually.
## Setting Values on a Contact
Custom field values are set in the **Edit Contact** modal:
- **Text / Number** - type directly into the field
- **Select** - choose from the dropdown
- **Date** - pick from the date picker
Leave a field blank to clear it.
## Importing Custom Field Data
When importing contacts via [[CSV Import]], you can map CSV columns to custom field definitions in the **Custom Field Mapping** step. For select-type fields, any unrecognised values trigger a **Select Value Resolution** step where you can skip, add, or remap each value.
## Filtering by Custom Fields
Custom field values can be used to filter contacts in the book. Use the filter panel to narrow contacts by any custom field value.
> [!success] The Key Idea
> Custom fields extend the contact record to fit your exact needs - whether that is a CRM status, a contract tier, a lead score, or anything else. Combine them with labels and filters to keep your book organized your way.
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**Next:** Learn how to populate custom fields on import with [[CSV Import]].