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Glossary· Approval workflows

Parallel Approval

Parallel approval is an approval pattern in which two or more reviewers receive the same request at the same time instead of waiting for one another. It is useful when several stakeholders need to review a request independently and there is no business reason to make those reviews sequential.

Simultaneous Independent reviewers receive the request together
Faster Reduce waiting between approval stages
Flexible Combine parallel and sequential stages
State-aware Move the request between review states and loops
Definition

Parallel approval is a workflow pattern where multiple approvers review a request simultaneously. The workflow waits for the required decisions according to the process rules, then moves the request to the next state or action.

In simple terms

Instead of Manager → Finance → Security, a parallel approval can send the request to Manager, Finance, and Security at the same time. If their reviews are independent, this can remove unnecessary waiting from the process.

How it works

What is parallel approval?

Parallel approval is used when more than one person or team needs to review the same request, but one reviewer does not need to wait for another reviewer’s decision. The requests are created together, each approver responds independently, and the workflow evaluates the combined result before continuing.

Request submitted Finance review Security review Business owner review Next action

This is different from sequential approval, where each approval stage waits for the previous one to finish. A mature approval workflow can use both patterns: parallel review where decisions are independent, followed by a sequential final authorization when required.

Example: new software request

An employee requests a new SaaS application. Finance can review the cost, Security can assess the risk, and the application owner can evaluate the business need at the same time. Once the required decisions are complete, the workflow can continue to Procurement or provisioning.

Why use it

Why use parallel approvals?

The main reason to use parallel approval is to remove artificial dependencies between reviewers. If three people can make their decisions independently, forcing reviewer two to wait for reviewer one simply extends the elapsed approval time.

Reduce approval time

Independent reviewers can work at the same time instead of adding their response times together.

Preserve specialist review

Finance, Legal, Security, IT, Procurement, or business owners can all contribute without creating a long sequential chain.

Support complex decisions

The workflow can wait until the required combination of decisions is complete before moving to the next stage.

Parallel does not mean uncontrolled

A parallel process still needs a clear rule for completion. Depending on the business process, the workflow might require all reviewers to approve, treat a single rejection as a stop condition, or apply another defined decision rule. The important point is that the reviewers can act independently while the workflow controls the combined outcome.

Use cases

Where are parallel approvals used?

Use case Parallel reviewers What happens next
Software purchase Finance + Security + Application owner Route to Procurement or provision the approved software
Vendor onboarding Security + Legal + Finance Create the vendor record or route exceptions for further review
Document review Legal + Compliance + Subject-matter experts Finalize, return for changes, or move to final sign-off. Google also supports file approvals in Google Drive for eligible Workspace accounts.
IT access request Resource owner + Security + Manager, where appropriate Provision access after the required approvals are complete
Employee onboarding HR + IT + Facilities / Operations Continue account, access, equipment, and workplace setup
Contract review Legal + Finance + Security / Privacy Route to an authorized signer or return for revision

Parallel reviews are particularly useful inside multi-level approvals. One level may contain several parallel reviewers, while the next level begins only after that group has completed its required decisions.

Parallel vs. sequential

Parallel approval vs. sequential approval

Question Sequential approval Parallel approval
When does each review start? After the previous required stage finishes Several reviews start at the same time
Best when Later reviewers depend on earlier decisions Reviewers can evaluate independently
Main risk One slow approver blocks everyone behind them The workflow still waits if one required parallel reviewer does not respond
Typical example Manager → Finance → Executive approval Finance + Security + Legal review together

The best design is often hybrid rather than choosing one pattern for the whole process. Approval routing can determine which reviews should run in parallel and which should remain dependent on an earlier decision.

Common hurdles

What are the common challenges of parallel approval?

1
The workflow does not define what “complete” means

The process must specify which combination of decisions allows the request to continue and what a rejection or request for changes does to the overall state.

2
One required reviewer still becomes a bottleneck

Parallel review removes waiting between reviewers, but the whole process can still stall if one required approver never responds.

3
Reviewers may work from different information

If request data or a document changes during review, different approvers may be evaluating different versions of the same object.

4
Conflicting decisions need a defined path

One team may approve while another rejects or requests changes. The workflow needs an explicit rule for how the object changes state.

5
Changes can trigger another review cycle

If the requester revises the item after feedback, some or all approvals may need to run again rather than continuing with stale decisions.

6
Too many parallel reviewers create approval fatigue

Parallelization should not become a reason to copy every possible stakeholder onto every request. Reviewers should be added only when their decision is required.

7
The final decision is disconnected from execution

Even after all approvals are complete, someone may still need to provision access, update a system, create a purchase order, or complete another business action manually.

Automation

How automation helps manage parallel approvals

Approval workflow software can create the approval requests simultaneously, track each reviewer’s state, apply the completion rules, send reminders, handle exceptions, and trigger the next business action when the required decisions are complete. Platforms such as Microsoft Power Automate also document approval automation patterns for business workflows.

Start reviews together

Create independent approval tasks at the same point in the workflow instead of forwarding the request manually.

Track each decision

Maintain the status of every required reviewer and evaluate the combined result automatically.

Handle non-response

Use deadlines, reminders, delegation, and escalation so one missing decision does not stay invisible.

Keep the approved object in a controlled state

Automation is especially valuable when the object being approved can change. A workflow can preserve a specific document version, hold an item in a review state, or route it back into a revision loop before approval starts again.

State machine

Using a state machine for approval loops

Zenphi allows teams to build state-machine-style automations where the object being approved moves between defined states. The general state-machine model is also widely used in workflow orchestration to represent discrete states and transitions. Instead of treating approval as one linear sequence, the workflow models what state the object is currently in and which events are allowed to move it to another state.

Example approval state machine
Draft Parallel Review Changes Requested Parallel Review Approved

If one reviewer requests a change, the object can move into a “Changes Requested” state. After the requester updates it, the workflow can loop the object back into review. If the required approvals are satisfied, it moves into the “Approved” state and the workflow continues.

This model is useful for contracts, policies, access requests, procurement items, documents, and other processes where a request may move backward as well as forward. It also makes the logic explicit: the same object is being switched between states, and the workflow controls which transition happens next.

With Zenphi

How Zenphi helps automate parallel approvals

Zenphi can combine parallel approvals with conditional routing, sequential stages, escalation logic, state transitions, and the business actions that happen after the final decision.

1
Start from the request channel

A workflow can begin from Google Forms, Jotform, Typeform, an internal portal, another system, or from Google Chat when a workflow is exposed as an enterprise AI agent.

2
Determine which reviewers are required

Use request data, department, amount, resource sensitivity, risk, requester role, or other conditions to decide which approval branches should exist.

3
Launch independent approvals in parallel

Reviewers who do not depend on one another can receive their approval tasks at the same time while Zenphi tracks their individual outcomes.

4
Move the object between states

A state-machine pattern can move the request through states such as Draft, In Review, Changes Requested, Approved, Rejected, or another process-specific state and loop it back for another review when necessary.

5
Handle delayed or conflicting outcomes

Use reminders, expiry, escalation, routing rules, and transition logic to determine what happens when a reviewer does not respond or when the parallel decisions do not align.

6
Execute the final business action

Once the required state is reached, Zenphi can continue into Google Workspace or external systems — for example, provision access, update permissions, create records, generate documents, create a purchase order, process a payment, or notify stakeholders.

Build with AI

Describe the approval logic in plain English with ZAIA

You do not have to start by manually drawing every branch. With ZAIA, Zenphi’s AI workflow builder, you can describe the automation you want in plain English — for example: “Send the request to Finance and Security in parallel. If either requests changes, move the item to Changes Requested. When it is resubmitted, run the reviews again. If the required approvals are complete, move it to Approved.” ZAIA can use that description to build a workflow draft that you can review and refine.

Examples from practice

Examples of parallel approval patterns

IT access

Send a sensitive access request to the resource owner and Security together, then provision access only after the required decisions are complete.

Procurement

Run Finance, Security, and Legal reviews together, then move the vendor or purchase into the next state when the review criteria are satisfied.

Document approval

Send a policy or contract to several subject-matter reviewers, collect feedback, move to Changes Requested if necessary, and loop back after revision.

Employee onboarding

Run HR, IT, and operational setup work in parallel after the appropriate authorization rather than waiting for one team to finish before another can begin.

Bring us one approval process that keeps waiting on people. We’ll map it with you in 30 minutes.

Bring a real process that currently runs through email, forms, spreadsheets, or manual follow-up. We’ll identify which reviews can run in parallel, where state transitions or loops are needed, and how to automate the actions that happen after approval.

Talk to an approval workflow expert
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Frequently asked questions

Frequently asked questions about parallel approvals

What is a parallel approval?

A parallel approval sends the same request to two or more independent reviewers at the same time rather than waiting for each person to respond in sequence. In Zenphi, parallel approval branches can be combined with routing rules, state changes, escalations, and the actions that follow the final decision.

What is the difference between parallel and sequential approval?

Sequential approval waits for one required review to finish before the next starts, while parallel approval starts several independent reviews together. Zenphi can combine both patterns in one workflow, so parallel reviews can be followed by a sequential final approval where the business process requires it.

When should parallel approval be used?

Parallel approval is most useful when several stakeholders need to review the same request but their decisions do not depend on one another. For example, a Zenphi workflow can ask Finance, Security, and an application owner to review a software request at the same time.

What happens if one parallel approver does not respond?

The workflow should define a deadline and escalation path for every required reviewer. In Zenphi, a delayed approval can trigger reminders, rerouting, escalation, or another defined state transition instead of leaving the overall request stuck without visibility.

What happens if parallel approvers disagree?

The workflow needs an explicit decision rule for conflicting outcomes. Depending on the process, a rejection may stop the request, send it to another reviewer, or move the object into a Changes Requested state. Zenphi can model this through conditional logic and state transitions.

Can parallel approvals loop back for another review?

Yes. This is a useful state-machine pattern. In Zenphi, an object can move from Parallel Review to Changes Requested and then loop back into review after it has been updated, rather than treating the workflow as a one-way approval chain.

What is a state machine in an approval workflow?

A state machine models the object being processed as a set of states and allowed transitions, such as Draft → In Review → Changes Requested → In Review → Approved. Zenphi can use this pattern for approval automations where items need to move forward, backward, or through repeated approval loops.

Can AI help build a parallel approval workflow?

Yes. Some workflow platforms provide AI-assisted building. In Zenphi, ZAIA lets users describe the desired automation in plain English and generates a draft workflow, which is useful when the process contains parallel branches, conditions, state changes, and approval loops.

Which tools can automate parallel approvals?

Parallel approval can be automated with workflow platforms such as Microsoft Power Automate, Zenphi, Kissflow, monday.com, Asana, and other business process automation tools. The best fit depends on the surrounding systems and how complex the routing and state logic needs to be. Zenphi is particularly relevant for teams using Google Forms, Docs, Drive, Sheets, Gmail, or Google Chat because the approval process can continue directly into Google Workspace and connected-system actions.

How can I make parallel approvals more efficient?

Include only genuinely independent reviewers, define the combined decision rule clearly, use deadlines and escalation, control the version being reviewed, and automate the next action. In Zenphi, those elements can be combined with parallel branches and state-machine logic in the same workflow.

Next step

Automate parallel approvals

Parallel approval can shorten complex review cycles without removing necessary oversight. The key is to parallelize decisions that are truly independent while defining exactly how the workflow responds to approvals, rejections, changes, and non-response.

Zenphi can combine parallel approvals with state-machine loops, conditional routing, escalation logic, Google Workspace actions, and connected business systems. ZAIA can also help teams get started by turning a plain-English workflow description into an initial automation draft.

Ana Bibikova
Written by

Ana Bibikova

Marketing and automation strategist specializing in translating complex workflows into clear, actionable content for modern organizations. Ana approaches automation from both a strategic and operational perspective, with a particular focus on scalable systems built on Google Workspace and cloud-based infrastructures.

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