What Is an SDR?

An SDR, or sales development representative, is a salesperson who works the top of the funnel: finding potential buyers, starting conversations, and booking qualified meetings for the reps who close.

Updated 28 October 2026 · Chronos Resources

Definition

A sales development representative (SDR) is an early-stage sales role dedicated to prospecting and qualification. Rather than closing deals, an SDR opens them: they build a list of accounts that fit the company's ideal customer profile, reach out across channels, qualify the people who respond, and pass the ready ones to an account executive for the sales conversation. The role exists because prospecting and closing demand different skills and a different pace, so most modern sales teams split the two.

SDRs sit at the very start of the revenue team. They are measured on top-of-funnel output, such as meetings booked, qualified opportunities created, and pipeline generated, rather than on closed revenue. That focus is the whole point: a dedicated prospecting role keeps the pipeline full so the rest of the team always has something to work.

What an SDR actually does

• Researches accounts and contacts that match the ideal customer profile (ICP).
• Runs outreach across email, LinkedIn, phone, and other channels.
• Qualifies inbound leads and outbound replies to confirm fit and genuine intent.
• Books meetings and discovery calls for account executives.
• Keeps the CRM current with notes, stages, and clear next steps.
• Hands off qualified prospects with enough context for the closer to pick up smoothly.

SDR vs. BDR

The titles SDR and BDR are often used interchangeably, and at many companies they describe the same work. Where teams do draw a line, an SDR usually handles and qualifies inbound leads, people who have already raised a hand, while a BDR focuses on outbound, net-new accounts that have shown no prior interest. The distinction varies by company, so it is always worth checking how a given team defines it. For the fuller breakdown, see what a BDR is.

Where an SDR fits in a modern outbound motion

In a modern go-to-market motion, the SDR is the engine at the top of the funnel. A clear ICP feeds the SDR a focused target list; the SDR personalizes outreach to each prospect, follows up on a cadence, and routes real interest to an AE. Done well, this keeps expensive closing reps focused on live conversations instead of cold prospecting, and it gives the company a predictable way to generate pipeline.

Increasingly, the repetitive mechanics of the role, list building, personalization at volume, sending, and follow-up tracking, are handled by software. An AI SDR can run that groundwork continuously and surface replies to a person, while human SDRs concentrate on judgment, rapport, and qualification calls. The two are complementary: the tooling creates consistent, personalized volume, and people handle the conversations that need a human.

Chronos works as a multi-channel AI SDR. It reads your website to build your ICP, sources and enriches buyers, writes a unique message per prospect, sends with deliverability safeguards, and runs follow-ups automatically, then surfaces replies for a human to take over. Every message is real AI-generated copy, never a template.

Frequently asked questions

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