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diff --git a/src/util/result.h b/src/util/result.h
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+// Copyright (c) 2022 The Bitcoin Core developers
+// Distributed under the MIT software license, see the accompanying
+// file COPYING or https://www.opensource.org/licenses/mit-license.php.
+
+#ifndef BITCOIN_UTIL_RESULT_H
+#define BITCOIN_UTIL_RESULT_H
+
+#include <attributes.h>
+#include <util/translation.h>
+
+#include <variant>
+
+namespace util {
+
+struct Error {
+    bilingual_str message;
+};
+
+//! The util::Result class provides a standard way for functions to return
+//! either error messages or result values.
+//!
+//! It is intended for high-level functions that need to report error strings to
+//! end users. Lower-level functions that don't need this error-reporting and
+//! only need error-handling should avoid util::Result and instead use standard
+//! classes like std::optional, std::variant, and std::tuple, or custom structs
+//! and enum types to return function results.
+//!
+//! Usage examples can be found in \example ../test/result_tests.cpp, but in
+//! general code returning `util::Result<T>` values is very similar to code
+//! returning `std::optional<T>` values. Existing functions returning
+//! `std::optional<T>` can be updated to return `util::Result<T>` and return
+//! error strings usually just replacing `return std::nullopt;` with `return
+//! util::Error{error_string};`.
+template <class T>
+class Result
+{
+private:
+    std::variant<bilingual_str, T> m_variant;
+
+    template <typename FT>
+    friend bilingual_str ErrorString(const Result<FT>& result);
+
+public:
+    Result(T obj) : m_variant{std::in_place_index_t<1>{}, std::move(obj)} {}
+    Result(Error error) : m_variant{std::in_place_index_t<0>{}, std::move(error.message)} {}
+
+    //! std::optional methods, so functions returning optional<T> can change to
+    //! return Result<T> with minimal changes to existing code, and vice versa.
+    bool has_value() const noexcept { return m_variant.index() == 1; }
+    const T& value() const LIFETIMEBOUND
+    {
+        assert(has_value());
+        return std::get<1>(m_variant);
+    }
+    T& value() LIFETIMEBOUND
+    {
+        assert(has_value());
+        return std::get<1>(m_variant);
+    }
+    template <class U>
+    T value_or(U&& default_value) const&
+    {
+        return has_value() ? value() : std::forward<U>(default_value);
+    }
+    template <class U>
+    T value_or(U&& default_value) &&
+    {
+        return has_value() ? std::move(value()) : std::forward<U>(default_value);
+    }
+    explicit operator bool() const noexcept { return has_value(); }
+    const T* operator->() const LIFETIMEBOUND { return &value(); }
+    const T& operator*() const LIFETIMEBOUND { return value(); }
+    T* operator->() LIFETIMEBOUND { return &value(); }
+    T& operator*() LIFETIMEBOUND { return value(); }
+};
+
+template <typename T>
+bilingual_str ErrorString(const Result<T>& result)
+{
+    return result ? bilingual_str{} : std::get<0>(result.m_variant);
+}
+} // namespace util
+
+#endif // BITCOIN_UTIL_RESULT_H