Oct 08, 2026 by Offer

What is market making (How To Answer): Interview Answer Guide 2027

To answer this market making interview question, define the role in one line (quote both sides, earn the spread), explain the two risks that eat the profit — inventory risk and adverse selection — and describe the defenses: skewing quotes, hedging, and widening spreads when volatility rises. Spread math plus risk management is the complete answer.

What This Market Making Interview Question Tests

A market maker is a liquidity provider: instead of betting on direction, they continuously quote a two-sided market — a bid price at which they'll buy and a slightly higher ask price at which they'll sell — and earn the bid-ask spread on the flow that trades against them. Exchanges and venues often designate market makers with obligations to quote; in return they get fee rebates or priority. The business model is volume times spread: tiny margins per trade, repeated thousands of times a day, with speed and automation doing the heavy lifting in modern electronic markets.

How to Answer This Market Making Interview Question

Define the business in one line — provide liquidity by quoting both sides, earn the spread — then immediately name the two risks: inventory accumulation and adverse selection from informed flow. One line each on why they hurt: inventory is unwanted directional exposure; informed traders trade only when your quote is wrong.

Then describe the three defenses as the craft: skew quotes to manage inventory, hedge what remains, widen spreads in volatile or uncertain conditions. Close with the P&L equation — spread captured minus adverse selection minus hedging costs — and the observation that modern making is a technology arms race on speed. Business model, risks, defenses, economics: that structure covers everything.

Common Mistakes on the Market Making Interview Question

Calling it risk-free profit. The spread is gross revenue; adverse selection and inventory losses are the costs. “Free money” framing reveals zero understanding of the business.

Ignoring adverse selection. The deepest risk isn't volatility — it's that your counterparty knows something you don't. Every market making answer needs the informed-trader problem.

Forgetting the technology dimension. Modern making is latency, data, and automation. Describing it as a human shouting quotes belongs to a different century.

This is the kind of technical question that commonly decides interview rounds — candidates report that one hesitant or rambling answer here can end the process on the spot. Practice saying your answer out loud until it sounds calm, structured, and confident.

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FAQ

How do market makers actually make money?

Primarily the bid-ask spread on customer flow, plus exchange rebates for providing liquidity — high volume on thin margins, minus losses to informed traders and hedging costs.

What is adverse selection in market making?

Losing systematically to better-informed counterparties, who trade against your quotes only when they're stale in their favor. It's the central cost of the business and the reason spreads exist.

Why do spreads widen in volatile markets?

Because the risk of quotes going stale (adverse selection) and of holding inventory both rise with volatility — wider spreads compensate the maker for the extra risk.

What's the difference between a market maker and a proprietary trader?

Market makers profit from facilitating flow (spread and rebates) while staying neutral; prop traders profit from directional bets. Interview format may vary by role and region — check the official careers page for the current process.

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