You have four weeks to close commercial due diligence, and the most important questions – why customers stay, who actually wins tenders, whether contracts will be renewed next year – are not answered in any market report or data room. The answers may lie with the company’s customers, former customers, competitors, and distributors, but contact with them must be managed in a way that does not disclose the confidential context of the transaction. Due diligence interviews are precisely the methodology for this: obtaining primary data from the company’s external environment without disclosing the transaction, provided this complies with the law, disclosure obligations, and arrangements with the respondent. Below is a description of the method – how to design the sample, formulate the invitation and the first question, verify what has been heard, and identify the boundaries of this type of fieldwork.
When are due diligence interviews a necessary source of answers?
Secondary data – industry reports, financial statements, tender databases, and registers – answer questions about market size and structure. They usually do not directly answer questions about the behavior of specific entities toward a specific company. This is why due diligence interviews are used when the quality of relationships, rather than market scale alone, needs to be verified.
Typical research questions that often cannot be resolved using secondary data alone include:
- Revenue durability – how customers describe their purchasing plans for the next budget cycle, what conditions would need to arise for them to change suppliers, and whether the decision to renew a contract is made by the same person with whom the company maintains the relationship.
- Actual position in procurement processes – which companies the target company is compared with in requests for proposals, at what stage it drops off the shortlist, and which criteria determine the outcome.
- The cost of changing suppliers – whether it results from technical integration, certification, operational teams’ habits, or price alone.
- Reasons for churn – former customers may be one of the most informative respondent groups in the entire project, yet they are often overlooked because they are not included on the list provided by the company.
- Channel behavior – distributors, integrators, and implementation partners can discuss margins, availability, and competition in ways that neither the company nor its end customer will.
Due diligence interviews operate under two constraints at the same time, and this combination is what defines transaction fieldwork as a distinct methodology. The first constraint is time: the fieldwork window is usually two to four weeks, often less, and recruiting B2B decision-makers at this pace requires several outreach channels to be run in parallel. The second is confidentiality in research: asking about a company in the wrong way can itself create a signal in the market – a customer may call their account manager, a competitor may begin to assess who could be for sale, and the information may reach the company’s management before an interview has even been conducted.
This is why transaction projects separate two layers: the substantive layer, meaning what needs to be established, and the description of the study presented to the respondent. The objective is not to mislead, but to describe the purpose of the study in a way that is factually accurate, does not disclose a confidential transaction, and fulfills disclosure obligations toward respondents.
How should transaction fieldwork be designed and conducted step by step?
The process consists of five stages that partly overlap in a transaction project – analysis begins before recruitment is complete because the first interviews reshape the discussion guide for subsequent ones.
1. Mapping the external environment and constructing the sample. The starting point is not a contact list from the company, as such a list may be biased – it usually includes active customers rather than the full spectrum of relationships. The sample is built independently using tender registers, company databases, public procurement data, LinkedIn signals, industry trade show attendee lists, public references on the websites of the company and its competitors. The target sample structure should include several layers: active customers of different sizes and relationship tenures, lost customers, competitors’ customers who have never been served by the company, channel participants, and industry experts. Proportions are determined by the research questions, not by respondent availability.
2. Study description and invitation script. The invitation has one task: to obtain informed consent for the conversation without disclosing the confidential context of the transaction. A sector-based framing works well – a study of purchasing practices, supplier selection criteria, and trends in a given segment – in which the company being analyzed is one of many entities mentioned, rather than the starting point. The invitation must include clear information on how statements will be used, the expected length of the conversation, the entity conducting the study, and any legally required information on the processing of personal data.
3. A discussion guide with a reversed sequence. The key difference between a standard in-depth interview and a transaction interview concerns the order of questions. The conversation begins at the category level: what the purchasing process looks like, who is involved in it, and which criteria carry weight. The respondent then names suppliers they know and have considered. Only then is the topic concerning the company explored in more depth – at that point, it is a natural continuation of the respondent’s own statement rather than a question imposed by the researcher.
In transaction projects, how the first question is asked can determine whether the respondent stays in the conversation at all – if the opening sounds like an assessment of a single supplier, the respondent may switch into a mode of cautious politeness and limit the scope of information provided.
4. Fieldwork delivery and ongoing triangulation. Interviews are conducted by phone or remotely, in the form of an in-depth interview (IDI), with a structured note completed according to a consistent template so that data from different conversations can be compared. In transaction fieldwork, analysis does not wait until the end: after the first wave of interviews, it is verified which hypotheses are being confirmed, and subsequent conversations are redirected toward disputed issues. Each statement presented as fact – contract value, number of bidders, discount level – should, where possible, be confirmed by at least two independent sources or reported with a note that it comes from a single interview.
5. Reporting while maintaining anonymity. Statements are described through respondent characteristics (segment, size, role in the purchasing process, relationship tenure), never by company or individual name, if this was promised during recruitment and if doing so does not enable the respondent to be identified indirectly. The report should clearly distinguish between what respondents said and the researcher’s interpretation, and indicate the level of certainty for each conclusion.
It is worth distinguishing between two modes of work that are sometimes confused. Customer references are conversations based on a contact list provided by the company, usually conducted openly at a later stage of the process and with management approval – they provide depth but are generally not representative. Independently recruited interviews with the company’s customers provide a picture that a reference list will not reveal, including reasons for churn and concerns expressed without relationship pressure. Both modes may be used in a well-designed project, but in a different sequence and with different evidentiary status.
What most often undermines transaction fieldwork?
Errors in due diligence interviews rarely result from a lack of experience in conducting conversations. They result from time pressure, which encourages shortcuts in sample design and verification:
- A sample based on a list from the company. The fastest route to recruitment may also lead to a positively skewed picture. A list from the company can be one source, but it should not be the only one.
- An overly detailed or inaccurate study description. The more elaborate the pretext, the easier it is to challenge. An effective study description is simple, truthful, and resilient to follow-up questions, and before the start, the researcher must have an agreed response with the client that complies with the law and the information provided to respondents.
- Asking about the company at the outset. This may trigger a focusing effect: the respondent begins to assess one entity separately from the set of alternatives while also realizing that the study concerns that particular company.
- Treating competitors’ statements as factual data. A competitor is a good source of information on market mechanics, channel structure, and tender logic. It is a weaker source of information on market shares and the performance of the company being assessed. Interviews with competitors should be conducted within the boundaries of competition law and without obtaining information covered by trade secrets.
- Too few interviews in narrow segments. If two conversations have been conducted in a segment, there is usually no basis for a firm conclusion about the entire segment – there is material for formulating a hypothesis that must be marked as unconfirmed.
- Neglecting lost customers. They are more difficult to recruit, so under time pressure they are the first to drop out of the sample. This may significantly distort the assessment of revenue retention risk.
- No audit trail. Notes without the date, respondent role, and recruitment method make it more difficult to defend conclusions later when the report is challenged.
An alternative to qualitative fieldwork is sometimes a short CATI survey on a broad sample of category customers. It can provide quantifiable distributions of preferences and awareness and, with an appropriately designed questionnaire, can reduce the risk of disclosing that one company is the subject of interest, because questions about it are only some of many questions. However, it does not provide the same understanding of decision-making mechanics or the conditions under which a customer would change suppliers. In practice, mixed-methods projects combine both modes: in-depth interviews establish hypotheses and respondents’ language, while the quantitative wave tests them. With a short time window, the decisive factor is whether the research question concerns why (qualitative fieldwork) or how many (quantitative fieldwork).
How can a provider’s readiness for transaction fieldwork be assessed?
When selecting a partner for due diligence interviews, it is worth verifying several specific elements before deciding to launch the project:
- Confidentiality procedure. Does the provider use NDAs covering the project team and recruitment subcontractors, maintain a register of individuals with access to project information, and secure recordings and transcripts?
- An agreed study description. Before fieldwork begins, is there a written and approved version of the communication with respondents, including answers to questions such as “who is commissioning this?” and “where did you get my number?”, which complies with disclosure obligations and personal data processing requirements?
- Independent recruitment. Can the provider build a sample without a list from the company, and what sources does it use to identify former customers?
- Sample structure before launch, not afterward. Does it provide a sample plan broken down by segment, including a minimum number of interviews in each segment and rules for reporting segments that have not been completed?
- Fieldwork pace. How many interviews per week are realistically achievable in a given industry, and how does the provider intend to achieve this – through the number of recruiters, incentives, or outreach channels?
- How uncertainty is reported. Does the report distinguish between repeatedly confirmed facts, individual opinions, and the researcher’s interpretation?
- Compliance with the law and standards. Is respondent data processed in accordance with GDPR, and does the provider declare compliance with industry standards, including a prohibition on obtaining information that constitutes a trade secret or competitively sensitive confidential information?
In practice, the greatest time savings in transaction fieldwork do not come from shortening interviews, but from preparation before launch: a closed list of research questions, a ready sample structure, and an agreed study description shorten recruitment more than any optimization during fieldwork.
Frequently asked questions
How can transaction confidentiality be maintained during interviews?
Confidentiality rests on three elements: a neutral study framing (a sector topic in which the company being analyzed is one of many possible entities), intermediation by an independent research institute, and control over the flow of information on the provider’s side – a named access register, NDAs for recruiters, and secure storage of recordings. This does not exempt the provider from disclosure obligations under personal data protection regulations or from the obligation to provide respondents with truthful information. In addition, it is worth limiting the number of interviews in very small segments, where the sample itself could reveal the subject of interest.
Who should be interviewed as part of due diligence?
The core of the sample consists of purchasing decision-makers among active customers, lost customers, and customers served exclusively by competitors – this third group shows how the company is perceived externally. The supplementary layer includes distributors and implementation partners, former employees of sales departments in the industry, and sector experts. Interviews with former employees should exclude obtaining information covered by confidentiality obligations or trade secrets. Selection should reflect the company’s revenue structure, not the ease of reaching respondents.
How many interviews are enough for conclusions to be credible?
The number depends on the number of segments, not an overall threshold. The practical rule is that, in every segment for which the report draws a conclusion, enough conversations are needed for content saturation to emerge – subsequent interviews do not introduce new themes but only confirm earlier ones. In highly concentrated markets, where a few customers account for most revenue, the criterion is different: coverage of key relationships matters, not the number of interviews.
Ask about fieldwork delivery in a transaction project
If a planned project requires conversations with the company’s external environment while maintaining confidentiality and working within a short time window, Hume’s Institute will prepare a sample plan, study description, and fieldwork schedule tailored to the specific research questions. Contact us to discuss the scope and realistic delivery pace in a given industry.