> ## Documentation Index
> Fetch the complete documentation index at: https://docs.junction.com/llms.txt
> Use this file to discover all available pages before exploring further.

# Introduction

> Introduction to the Junction Lab Testing API for ordering lab tests, managing results, and integrating with physician networks and partner labs.

Junction's Lab Testing API lets you create lab orders, coordinate sample collection, monitor order progress, and retrieve results from partner laboratories through one integration.

## Core concepts

* A **user** represents the patient receiving the test.
* A **lab test** defines the markers to order, the partner laboratory, and the supported collection methods. See [Creating a Lab Test](/lab/workflow/create-test).
* An **order** represents one lab test performed for one patient. Its status progresses from order creation through collection and results. See [Order Status and Lifecycle](/lab/workflow/lab-test-lifecycle).
* An **order transaction** represents one patient testing journey and groups the initial order with related orders, such as redraws. See [Order Transactions](/lab/workflow/order-transactions).
* A **lab account** defines the laboratory configuration and supported billing types used to place an order. See [Lab Accounts](/lab/overview/lab-accounts).
* A **result** is available as structured data and, when provided by the laboratory, a PDF report. See [Results Overview](/lab/results/overview).

## Integration workflow

1. Choose how the patient's sample will be collected. Compare the available [testing modalities](/lab/overview/testing-modalities).
2. Determine which laboratory, tests, billing types, and physician workflow your program requires. See [Choosing Tests and Markers](/lab/workflow/ordering), [Lab Accounts](/lab/overview/lab-accounts), and [Order and Follow-up Physician](/lab/overview/physicians).
3. Create the patient and place an order by following the [Quickstart](/lab/overview/quickstart) guide.
4. Follow the end-to-end [Orders and Results](/lab/overview/orders-and-results) guide to monitor the order, retrieve results, and handle follow-up states. If enabled, Junction can also send [patient email and SMS communications](/lab/workflow/communications).

## Sandbox and production

Use the sandbox environment to create test orders, simulate lifecycle transitions, verify webhook handling, and test patient communications. See [Testing in Sandbox](/lab/overview/sandbox).

Sandbox and production have separate API keys and Team configuration. Before placing production orders, confirm that your production Team has the required lab tests, lab accounts, billing types, physician workflow, collection coverage, and communications settings.

## Coverage

Coverage varies by testing modality, partner laboratory, and patient location. Use the [Area Info endpoint](/api-reference/lab-testing/area-info) to check services for a ZIP code.

For help planning or enabling a production workflow, [contact Junction support](/home/getting-support).


## Related topics

- [Introduction](/webhooks/introduction.md)
- [Introduction to Link](/wearables/connecting-providers/introduction.md)
- [Order Status and Lifecycle](/lab/workflow/lab-test-lifecycle.md)
- [Webhooks and Events](/api-reference/org-management/connect/webhooks-and-events.md)