Trading and Exchanges

About the book

Trading and Exchanges is a systematic treatment of market structure by Larry Harris, a finance academic who spent years inside the institutions he describes. It addresses a question that most investing books skip: once someone decides to buy or sell, what machinery stands between the intention and the executed trade, and what does that machinery cost?

Harris works through the participants and the mechanics they use. He covers the intermediaries who arrange trades, the order types available to customers, the dealers who quote prices and hold inventory, and the liquidity traders and informed traders whose interaction determines spreads. Exchanges and alternative trading venues appear as designs with consequences, and Harris examines how rules on transparency, priority and price continuity affect who trades where and on what terms.

The scope extends to the economics underneath: why bid-ask spreads exist, how competition among venues changes execution quality, and what happens when regulation reshapes the incentives of brokers and dealers. Harris writes as an economist explaining institutions, so the emphasis falls on why arrangements persist and what they cost.

How to read it

Approach the book as a reference to work through in sections. The prose is clear and largely free of mathematics, but the density comes from terminology and institutional detail. Keep the glossary close and expect to reread passages on order priority and dealer inventory once the surrounding context is in place.

Pay attention to the examples, which carry much of the argument. Harris uses concrete market situations to show how a rule or an incentive produces a particular outcome, and the reasoning is easier to follow when you trace each example against the definitions established earlier. Readers who want the conceptual skeleton can move faster through the descriptive material on specific market institutions.

Who it suits

This suits readers who already understand basic finance and want to know how execution works beneath the level of picking securities: students of market microstructure, professionals in trading or operations who need the institutional picture, and general readers curious about why trading costs differ across venues. It rewards patience with a durable framework for thinking about market design.

Reading considerations

Electronic trading, venue fragmentation and regulatory structures have changed substantially since the book appeared, so treat the institutional descriptions as a foundation to update rather than a current map. The book explains how markets work; it does not offer investment advice, and readers seeking strategy guidance should look elsewhere.