When you're ready to hire an evaluator or build your evaluation framework, a solid Request for Proposal (RFP) is the difference between getting what you actually need and paying for something that sits on a shelf. An RFP forces vendors to be specific about methodology, cost, and deliverables—and it forces you to think clearly about what success looks like for your nonprofit. This guide walks you through what to include and what to demand answers to.
Start with a Clear Scope Statement
Your RFP's scope section should define exactly what you're measuring. Don't write "evaluate our program's impact." Instead, specify: "Evaluate the employment outcomes of our 12-week workforce development program serving formerly incarcerated adults in three counties over a 24-month period. Primary outcome: sustained employment (30+ hours/week) at six, twelve, and eighteen months post-exit."
Include your target sample size, evaluation period, and geographic boundaries. State whether you want rigorous experimental design (randomized control trial, regression discontinuity) or a quasi-experimental or descriptive approach. This clarity tells vendors what complexity they're pricing.
Define Methodology Expectations
Evaluation firms use wildly different approaches, and the methodology drives cost and timeline dramatically. Your RFP should ask vendors to:
- Describe their proposed design (comparison group, outcome measurement approach, data collection frequency)
- Justify why that design fits your budget and timeline
- Specify which outcomes they'll measure (employment rate, wage, retention, client satisfaction, cost per outcome, etc.)
- Outline their process for managing and analyzing data
- Explain how they'll handle common issues: attrition, missing data, selection bias
Ask for concrete examples of similar evaluations they've completed. A vendor citing workforce development evaluations in similar geographies with similar sample sizes is more relevant than broad experience across fifteen different program types.
Budget and Timeline
Be upfront about your budget range. Quality impact evaluation typically runs $15,000–$75,000+ depending on complexity and sample size. A rigorous RCT with 300+ participants, baseline and multiple follow-ups, and statistical analysis costs considerably more than a single-timepoint survey of 75 program participants.
Request vendors to provide:
- Detailed line-item cost breakdown (data collection, analysis, reporting, staff time)
- Timeline from RFP acceptance to final report delivery
- Any contingency costs (additional follow-up waves, expanded sample, additional sites)
- Payment schedule (typically monthly or by milestone)
Data and Reporting Deliverables
Specify exactly what you want to receive. Generic requests lead to generic reports. Instead, ask for:
- Codebook and raw data in [specified format, usually CSV or SPSS]
- Statistical output files and analysis scripts
- Report format and length (many nonprofits want a 15-page executive summary, not a 100-page technical document)
- Visualizations or dashboards if needed
- Rights to use findings publicly and for grant applications
Clarify who owns the data and whether the evaluator will maintain it, update it, or provide it to you for storage. Ask whether the vendor will support follow-up analyses or additional questions after the report is delivered, and at what cost.
Vendor Qualifications and Experience
Ask for:
- Staff credentials (relevant degrees, certifications, years in evaluation)
- References from three similar nonprofits or funders (call them)
- Evidence of experience with your program type and population
- Conflicts of interest (do they evaluate competitors? do they receive funding from your funder?)
- Approach to culturally responsive evaluation
Questions About Data Security and Ethics
Nonprofits and their clients deserve protection. Request that vendors explain:
- How they ensure participant confidentiality and comply with relevant regulations
- Their protocol for informed consent
- IRB approval (internal review board) or approach to ethical oversight
- Data security practices (encryption, storage location, retention policy)
Comparison and Selection
Platform tools like Mercoly help you compare and find trusted impact measurement and evaluation providers in one place, making it easier to see how proposals stack up side-by-side.
When you receive proposals, don't just compare price. Score vendors against criteria that matter: methodological rigor, relevant experience, timeline feasibility, and your gut sense of whether they understand your program's theory of change.
Frequently Asked Questions
Q: What's the difference between outcome evaluation and impact evaluation, and which should I request? Outcome evaluation measures whether participants achieved intended results (did beneficiaries get employed?). Impact evaluation adds a counterfactual—would they have gotten employed anyway? Impact is harder and more expensive but answers the causal question funders care about.
Q: How long should an impact evaluation take? A simple retrospective outcome survey of existing participants takes 3–4 months. A rigorous evaluation with baseline data collection, 12-month follow-up, and control group can take 18–24 months before final results.
Q: Can we do this cheaper in-house? You can conduct basic surveys and track outcomes internally, but rigorous impact evaluation requires statistical expertise and external credibility that external evaluators provide. Consider hybrid models: you collect data, a vendor designs and analyzes.
Start drafting your RFP with these sections, and you'll attract evaluators who take your impact seriously.