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diff --git a/include/opentracing/tracer_factory.h b/include/opentracing/tracer_factory.h
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+++ b/include/opentracing/tracer_factory.h
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+#ifndef OPENTRACING_TRACER_FACTORY_H
+#define OPENTRACING_TRACER_FACTORY_H
+
+#include <opentracing/symbols.h>
+#include <opentracing/tracer.h>
+#include <opentracing/version.h>
+
+namespace opentracing {
+BEGIN_OPENTRACING_ABI_NAMESPACE
+// Returns the std::error_category class used for tracer factory errors.
+//
+// See
+//   http://blog.think-async.com/2010/04/system-error-support-in-c0x-part-1.html
+//   https://ned14.github.io/boost.outcome/md_doc_md_03-tutorial_b.html
+OPENTRACING_API const std::error_category& tracer_factory_error_category();
+
+// `configuration_parse_error` occurs when the configuration string used to
+// construct a tracer does not adhere to the expected format.
+const std::error_code configuration_parse_error(
+    1, tracer_factory_error_category());
+
+// `invalid_configuration_error` occurs if the requested configuration for a
+// tracer has invalid values.
+const std::error_code invalid_configuration_error(
+    2, tracer_factory_error_category());
+
+// TracerFactory constructs tracers from configuration strings.
+class OPENTRACING_API TracerFactory {
+ public:
+  virtual ~TracerFactory() = default;
+
+  // Creates a tracer with the requested `configuration`.
+  //
+  // Example,
+  //   const char* configuration = R"(
+  //      "collector": "localhost:123",
+  //      "max_buffered_spans": 500
+  //   )";
+  //   std:string error_message;
+  //   auto tracer_maybe = tracer_factory->MakeTracer(configuration,
+  //                                                  error_message);
+  //   if (tracer_mabye) {
+  //      // success
+  //      std::shared_ptr<opentracing::Tracer> tracer = *tracer_maybe;
+  //   } else {
+  //      // failure
+  //      std::error_code error = tracer_maybe.error();
+  //      // `error_message` may also contain a more descriptive message
+  //   }
+  virtual expected<std::shared_ptr<Tracer>> MakeTracer(
+      const char* configuration, std::string& error_message) const noexcept = 0;
+};
+END_OPENTRACING_ABI_NAMESPACE
+}  // namespace opentracing
+
+#endif  // OPENTRACING_TRACER_FACTORY_H