Enterprise buyers use questionnaires to understand a vendor's controls, data handling and ability to manage risk. The workbook may be a recognised industry format or an assessment designed by the buyer. Knowing the difference helps a startup organise evidence without assuming that one completed spreadsheet automatically answers every future review.
If you want an expert team to manage a response, see our security questionnaire support service. A questionnaire often sits alongside a call and evidence request; our customer security review support covers that wider process.
What is SIG?
The Standardised Information Gathering questionnaire is maintained by Shared Assessments for third-party risk assessments. It is designed to help an assessor examine a service provider across multiple risk domains rather than only one technology layer. Depending on the version and buyer selection, topics can include governance, information security, privacy, resilience, suppliers, cloud services and AI.
SIG Lite is a shorter route for lower-risk or less complex assessments. The full SIG can be extensive, with conditional questions and a significant evidence burden. The important preparation is not memorising every row: it is knowing your scope, control owners, current policies and supporting records.
What is CAIQ?
The Consensus Assessments Initiative Questionnaire is associated with the Cloud Security Alliance and focuses on cloud security practices. Its questions are useful when a buyer wants a structured view of how a cloud service operates, protects data and manages its cloud responsibilities. A CAIQ request may be paired with other assurance material, such as a security report or architecture explanation.
CAIQ should not be treated as a certification. Read each question against your actual service model: SaaS provider, infrastructure provider and customer-managed deployment have different boundaries. Document shared-responsibility assumptions so a buyer can see which controls you operate and which belong to its environment.
What are custom enterprise questionnaires?
A custom questionnaire is created by the buyer or its procurement, security, privacy or legal team. It may be a spreadsheet, portal, document or series of follow-up questions. Custom reviews often reflect a buyer's sector, contract requirements, data sensitivity, geography and threat model. A regulated enterprise may ask for detailed incident notification, resilience, subcontractor, data residency or AI governance answers even when a standard format does not.
Custom does not mean arbitrary. Most questionnaires revisit familiar themes: access, encryption, vulnerability management, secure development, continuity, privacy, people, suppliers and incident response. Map the buyer's wording to your controlled answer bank, then answer the question asked rather than pasting a generic paragraph.
Key differences in scope and format
- Ownership: SIG comes from Shared Assessments, CAIQ from CSA, while custom forms belong to the buyer.
- Primary lens: SIG is broad third-party risk; CAIQ is cloud-focused; custom forms reflect a buyer-specific risk decision.
- Format: Standard questionnaires often have defined answer choices and conditional sections. Custom portals may impose character limits, attachments or buyer-specific statuses.
- Depth: Any format can be short or extensive. Risk, product complexity and buyer requirements matter more than the label.
- Evidence: All three may request policies, reports, diagrams, testing records or explanations. Permission and confidentiality must be checked before sharing.
How a startup should prepare
Start with a service boundary: products, environments, data types, hosting regions, subprocessors and customer responsibilities. Then maintain a control inventory with an owner, status and evidence source. Write a plain-language description for recurring topics, including authentication, privileged access, secure development, vulnerability management, backup, incident response, retention and deletion.
For SIG, practise mapping your controls across many domains and prepare evidence descriptions that explain scope. For CAIQ, document cloud architecture and the division of responsibility between your service and the customer. For custom assessments, build a clarification process and expect the buyer to ask questions that are specific to its contract or use case.
In every case, answer “yes” only when the control operates as described. A partial or negative answer with a clear boundary is more useful than a broad claim that later conflicts with a policy, report or security call. Keep version dates and review answers after changes to vendors, architecture, policies or certification scope.
Frequently asked questions
Is SIG the same as CAIQ?
No. SIG is a Shared Assessments third-party risk questionnaire family, while CAIQ is a Cloud Security Alliance questionnaire aligned to cloud controls. A buyer chooses based on its risk process and the vendor service being assessed.
Which questionnaire should a startup complete first?
Complete the questionnaire requested by the buyer, then use it to build a reusable answer bank. A startup serving cloud customers should be ready for both cloud-focused CAIQ questions and broader SIG or custom reviews.
Can one answer bank support all questionnaire formats?
Yes, if the bank stores controlled answers, scope, evidence and source dates rather than copied workbook cells. Format-specific mappings are still needed because the same control may be phrased differently.
For the mechanics of answering, read how to answer a vendor security questionnaire. For maintaining reusable responses, see the answer-bank guide.