diff --git a/src/fb-cpp/Attachment.cpp b/src/fb-cpp/Attachment.cpp
index fafd876..df57b3f 100644
--- a/src/fb-cpp/Attachment.cpp
+++ b/src/fb-cpp/Attachment.cpp
@@ -31,7 +31,7 @@ using namespace fbcpp::impl;
 
 
 Attachment::Attachment(Client& client, const std::string& uri, const AttachmentOptions& options)
-	: client{client}
+	: client{&client}
 {
 	const auto master = client.getMaster();
 
@@ -68,8 +68,8 @@ void Attachment::disconnectOrDrop(bool drop)
 {
 	assert(isValid());
 
-	const auto status = client.newStatus();
-	StatusWrapper statusWrapper{client, status.get()};
+	const auto status = client->newStatus();
+	StatusWrapper statusWrapper{*client, status.get()};
 
 	if (drop)
 		handle->dropDatabase(&statusWrapper);
diff --git a/src/fb-cpp/Attachment.h b/src/fb-cpp/Attachment.h
index ba8d0e3..e325db2 100644
--- a/src/fb-cpp/Attachment.h
+++ b/src/fb-cpp/Attachment.h
@@ -192,7 +192,22 @@ namespace fbcpp
 		{
 		}
 
-		Attachment& operator=(Attachment&&) = delete;
+		///
+		/// @brief Transfers ownership of another Attachment into this one.
+		///
+		/// The old handle is released via `FbRef::operator=(FbRef&&)`.
+		/// After the assignment, `this` is valid (with `o`'s handle) and `o` is invalid.
+		///
+		Attachment& operator=(Attachment&& o) noexcept
+		{
+			if (this != &o)
+			{
+				client = o.client;
+				handle = std::move(o.handle);
+			}
+
+			return *this;
+		}
 
 		Attachment(const Attachment&) = delete;
 		Attachment& operator=(const Attachment&) = delete;
@@ -229,7 +244,7 @@ namespace fbcpp
 		///
 		Client& getClient() noexcept
 		{
-			return client;
+			return *client;
 		}
 
 		///
@@ -254,7 +269,7 @@ namespace fbcpp
 		void disconnectOrDrop(bool drop);
 
 	private:
-		Client& client;
+		Client* client;
 		FbRef<fb::IAttachment> handle;
 	};
 }  // namespace fbcpp
diff --git a/src/fb-cpp/CalendarConverter.h b/src/fb-cpp/CalendarConverter.h
index 5261bb4..32cb71f 100644
--- a/src/fb-cpp/CalendarConverter.h
+++ b/src/fb-cpp/CalendarConverter.h
@@ -49,7 +49,7 @@ namespace fbcpp::impl
 	{
 	public:
 		explicit CalendarConverter(Client& client, StatusWrapper* statusWrapper)
-			: client{client},
+			: client{&client},
 			  statusWrapper{statusWrapper}
 		{
 		}
@@ -67,7 +67,7 @@ namespace fbcpp::impl
 			if (yearValue <= 0)
 				throwInvalidDateValue();
 
-			return OpaqueDate{client.getUtil()->encodeDate(static_cast<unsigned>(yearValue), monthValue, dayValue)};
+			return OpaqueDate{client->getUtil()->encodeDate(static_cast<unsigned>(yearValue), monthValue, dayValue)};
 		}
 
 		Date opaqueDateToDate(OpaqueDate date)
@@ -76,7 +76,7 @@ namespace fbcpp::impl
 			unsigned month;
 			unsigned day;
 
-			client.getUtil()->decodeDate(date.value, &year, &month, &day);
+			client->getUtil()->decodeDate(date.value, &year, &month, &day);
 
 			return Date{std::chrono::year{static_cast<int>(year)}, std::chrono::month{month}, std::chrono::day{day}};
 		}
@@ -140,7 +140,7 @@ namespace fbcpp::impl
 			const auto subseconds = static_cast<unsigned>(time.subseconds().count() / 100);
 
 			OpaqueTime opaqueTime;
-			opaqueTime.value = client.getUtil()->encodeTime(hours, minutes, seconds, subseconds);
+			opaqueTime.value = client->getUtil()->encodeTime(hours, minutes, seconds, subseconds);
 
 			return opaqueTime;
 		}
@@ -152,7 +152,7 @@ namespace fbcpp::impl
 			unsigned seconds;
 			unsigned subseconds;
 
-			const auto util = client.getUtil();
+			const auto util = client->getUtil();
 			util->decodeTime(time.value, &hours, &minutes, &seconds, &subseconds);
 
 			const auto timeOfDay = std::chrono::hours{hours} + std::chrono::minutes{minutes} +
@@ -252,7 +252,7 @@ namespace fbcpp::impl
 
 			OpaqueTimeTz opaque{};
 
-			client.getUtil()->encodeTimeTz(statusWrapper, &opaque.value, 0u, 0u, 0u, 0u, timeTz.zone.c_str());
+			client->getUtil()->encodeTimeTz(statusWrapper, &opaque.value, 0u, 0u, 0u, 0u, timeTz.zone.c_str());
 
 			opaque.value.utc_time = static_cast<ISC_TIME>(duration.count() / 100);
 
@@ -269,7 +269,7 @@ namespace fbcpp::impl
 			unsigned fractions;
 			std::array<char, 128> timeZoneBuffer;
 
-			client.getUtil()->decodeTimeTz(statusWrapper, &opaqueTime.value, &hours, &minutes, &seconds, &fractions,
+			client->getUtil()->decodeTimeTz(statusWrapper, &opaqueTime.value, &hours, &minutes, &seconds, &fractions,
 				static_cast<unsigned>(timeZoneBuffer.size()), timeZoneBuffer.data());
 
 			TimeTz timeTz;
@@ -295,7 +295,7 @@ namespace fbcpp::impl
 			unsigned fractions;
 			std::array<char, 128> timeZoneBuffer;
 
-			client.getUtil()->decodeTimeTz(statusWrapper, &time.value, &hours, &minutes, &seconds, &fractions,
+			client->getUtil()->decodeTimeTz(statusWrapper, &time.value, &hours, &minutes, &seconds, &fractions,
 				static_cast<unsigned>(timeZoneBuffer.size()), timeZoneBuffer.data());
 
 			return std::format("{:02}:{:02}:{:02}.{:04} {}", hours, minutes, seconds, fractions, timeZoneBuffer.data());
@@ -360,7 +360,7 @@ namespace fbcpp::impl
 
 			OpaqueTimeTz encoded;
 			const std::string timeZoneString{makeComponentView(5)};
-			client.getUtil()->encodeTimeTz(
+			client->getUtil()->encodeTimeTz(
 				statusWrapper, &encoded.value, hours, minutes, seconds, fractions, timeZoneString.c_str());
 
 			return opaqueTimeTzToTimeTz(encoded);
@@ -389,7 +389,7 @@ namespace fbcpp::impl
 			OpaqueTimestamp opaqueTimestamp;
 			opaqueTimestamp.value.timestamp_date = opaqueDate.value;
 			opaqueTimestamp.value.timestamp_time =
-				client.getUtil()->encodeTime(static_cast<unsigned>(timestamp.time.hours().count()),
+				client->getUtil()->encodeTime(static_cast<unsigned>(timestamp.time.hours().count()),
 					static_cast<unsigned>(timestamp.time.minutes().count()),
 					static_cast<unsigned>(timestamp.time.seconds().count()), static_cast<unsigned>(subseconds / 100));
 
@@ -406,7 +406,7 @@ namespace fbcpp::impl
 			unsigned seconds;
 			unsigned subseconds;
 
-			const auto util = client.getUtil();
+			const auto util = client->getUtil();
 			util->decodeDate(timestamp.value.timestamp_date, &year, &month, &day);
 			util->decodeTime(timestamp.value.timestamp_time, &hours, &minutes, &seconds, &subseconds);
 
@@ -513,7 +513,7 @@ namespace fbcpp::impl
 		{
 			OpaqueTimestampTz opaque;
 
-			client.getUtil()->encodeTimeStampTz(
+			client->getUtil()->encodeTimeStampTz(
 				statusWrapper, &opaque.value, 1u, 1u, 1u, 0u, 0u, 0u, 0u, timestampTz.zone.c_str());
 
 			const auto utcOpaque = timestampToOpaqueTimestamp(timestampTz.utcTimestamp);
@@ -539,7 +539,7 @@ namespace fbcpp::impl
 			unsigned subseconds;
 			std::array<char, 128> timeZoneBuffer;
 
-			client.getUtil()->decodeTimeStampTz(statusWrapper, &opaqueTimestamp.value, &year, &month, &day, &hours,
+			client->getUtil()->decodeTimeStampTz(statusWrapper, &opaqueTimestamp.value, &year, &month, &day, &hours,
 				&minutes, &seconds, &subseconds, static_cast<unsigned>(timeZoneBuffer.size()), timeZoneBuffer.data());
 
 			TimestampTz timestampTz;
@@ -569,7 +569,7 @@ namespace fbcpp::impl
 			unsigned subseconds;
 			std::array<char, 128> timeZoneBuffer;
 
-			client.getUtil()->decodeTimeStampTz(statusWrapper, &timestamp.value, &year, &month, &day, &hours, &minutes,
+			client->getUtil()->decodeTimeStampTz(statusWrapper, &timestamp.value, &year, &month, &day, &hours, &minutes,
 				&seconds, &subseconds, static_cast<unsigned>(timeZoneBuffer.size()), timeZoneBuffer.data());
 
 			return std::format("{:04}-{:02}-{:02} {:02}:{:02}:{:02}.{:04} {}", year, month, day, hours, minutes,
@@ -648,7 +648,7 @@ namespace fbcpp::impl
 
 			OpaqueTimestampTz encoded;
 			const std::string timeZoneString{makeComponentView(8)};
-			client.getUtil()->encodeTimeStampTz(statusWrapper, &encoded.value,
+			client->getUtil()->encodeTimeStampTz(statusWrapper, &encoded.value,
 				static_cast<unsigned>(static_cast<int>(date.year())), monthValue, dayValue, hours, minutes, seconds,
 				fractions, timeZoneString.c_str());
 
@@ -674,7 +674,7 @@ namespace fbcpp::impl
 				isc_arg_end,
 			};
 
-			throw DatabaseException(client, STATUS_CONVERSION_ERROR_FROM_STRING);
+			throw DatabaseException(*client, STATUS_CONVERSION_ERROR_FROM_STRING);
 		}
 
 		[[noreturn]] void throwInvalidDateValue()
@@ -684,7 +684,7 @@ namespace fbcpp::impl
 				isc_arg_end,
 			};
 
-			throw DatabaseException(client, STATUS_INVALID_DATE_VALUE);
+			throw DatabaseException(*client, STATUS_INVALID_DATE_VALUE);
 		}
 
 		[[noreturn]] void throwInvalidTimeValue()
@@ -694,7 +694,7 @@ namespace fbcpp::impl
 				isc_arg_end,
 			};
 
-			throw DatabaseException(client, STATUS_INVALID_TIME_VALUE);
+			throw DatabaseException(*client, STATUS_INVALID_TIME_VALUE);
 		}
 
 		[[noreturn]] void throwInvalidTimestampValue()
@@ -704,7 +704,7 @@ namespace fbcpp::impl
 				isc_arg_end,
 			};
 
-			throw DatabaseException(client, STATUS_INVALID_TIMESTAMP_VALUE);
+			throw DatabaseException(*client, STATUS_INVALID_TIMESTAMP_VALUE);
 		}
 
 	private:
@@ -712,7 +712,7 @@ namespace fbcpp::impl
 		static constexpr auto BASE_EPOCH = std::chrono::local_days{
 			std::chrono::year{1858} / std::chrono::November / 17,
 		};
-		Client& client;
+		Client* client;
 		StatusWrapper* statusWrapper;
 	};
 }  // namespace fbcpp::impl
diff --git a/src/fb-cpp/Exception.cpp b/src/fb-cpp/Exception.cpp
index 6ea022e..2f9f94c 100644
--- a/src/fb-cpp/Exception.cpp
+++ b/src/fb-cpp/Exception.cpp
@@ -34,7 +34,7 @@ using namespace fbcpp::impl;
 void StatusWrapper::checkException(StatusWrapper* status)
 {
 	if (status->dirty && (status->getState() & fb::IStatus::STATE_ERRORS))
-		throw DatabaseException{status->client, status->getErrors()};
+		throw DatabaseException{*status->client, status->getErrors()};
 }
 
 void StatusWrapper::catchException(fb::IStatus* status) noexcept
diff --git a/src/fb-cpp/Exception.h b/src/fb-cpp/Exception.h
index fb62ddb..2203a4d 100644
--- a/src/fb-cpp/Exception.h
+++ b/src/fb-cpp/Exception.h
@@ -45,7 +45,7 @@ namespace fbcpp::impl
 	{
 	public:
 		explicit StatusWrapper(Client& client, IStatus* status)
-			: client{client},
+			: client{&client},
 			  status{status}
 		{
 		}
@@ -158,7 +158,7 @@ namespace fbcpp::impl
 		}
 
 	protected:
-		Client& client;
+		Client* client;
 		IStatus* status;
 		bool dirty = false;
 
diff --git a/src/fb-cpp/NumericConverter.h b/src/fb-cpp/NumericConverter.h
index d2eb81b..5cad647 100644
--- a/src/fb-cpp/NumericConverter.h
+++ b/src/fb-cpp/NumericConverter.h
@@ -148,7 +148,7 @@ namespace fbcpp::impl
 	{
 	public:
 		explicit NumericConverter(Client& client, StatusWrapper* statusWrapper)
-			: client{client},
+			: client{&client},
 			  statusWrapper{statusWrapper}
 		{
 		}
@@ -161,7 +161,7 @@ namespace fbcpp::impl
 				isc_arg_end,
 			};
 
-			throw DatabaseException(client, STATUS_NUMERIC_OUT_OF_RANGE);
+			throw DatabaseException(*client, STATUS_NUMERIC_OUT_OF_RANGE);
 		}
 
 		[[noreturn]] void throwConversionErrorFromString(const std::string& str)
@@ -172,7 +172,7 @@ namespace fbcpp::impl
 				isc_arg_end,
 			};
 
-			throw DatabaseException(client, STATUS_CONVERSION_ERROR_FROM_STRING);
+			throw DatabaseException(*client, STATUS_CONVERSION_ERROR_FROM_STRING);
 		}
 
 	public:
@@ -356,7 +356,7 @@ namespace fbcpp::impl
 
 		std::string opaqueInt128ToString(const OpaqueInt128& opaqueInt128, int scale)
 		{
-			const auto int128Util = client.getUtil()->getInt128(statusWrapper);
+			const auto int128Util = client->getUtil()->getInt128(statusWrapper);
 			char buffer[fb::IInt128::STRING_SIZE + 1];
 			int128Util->toString(statusWrapper, &opaqueInt128, scale, static_cast<unsigned>(sizeof(buffer)), buffer);
 			return buffer;
@@ -364,7 +364,7 @@ namespace fbcpp::impl
 
 		std::string opaqueDecFloat16ToString(const OpaqueDecFloat16& opaqueDecFloat16)
 		{
-			const auto decFloat16Util = client.getDecFloat16Util(statusWrapper);
+			const auto decFloat16Util = client->getDecFloat16Util(statusWrapper);
 			char buffer[fb::IDecFloat16::STRING_SIZE + 1];
 			decFloat16Util->toString(statusWrapper, &opaqueDecFloat16, static_cast<unsigned>(sizeof(buffer)), buffer);
 			return buffer;
@@ -372,7 +372,7 @@ namespace fbcpp::impl
 
 		std::string opaqueDecFloat34ToString(const OpaqueDecFloat34& opaqueDecFloat34)
 		{
-			const auto decFloat34Util = client.getDecFloat34Util(statusWrapper);
+			const auto decFloat34Util = client->getDecFloat34Util(statusWrapper);
 			char buffer[fb::IDecFloat34::STRING_SIZE + 1];
 			decFloat34Util->toString(statusWrapper, &opaqueDecFloat34, static_cast<unsigned>(sizeof(buffer)), buffer);
 			return buffer;
@@ -401,7 +401,7 @@ namespace fbcpp::impl
 
 		OpaqueDecFloat16 boostDecFloat16ToOpaqueDecFloat16(const BoostDecFloat16& boostDecFloat16)
 		{
-			const auto decFloat16Util = client.getDecFloat16Util(statusWrapper);
+			const auto decFloat16Util = client->getDecFloat16Util(statusWrapper);
 			OpaqueDecFloat16 opaqueDecFloat16;
 			decFloat16Util->fromString(statusWrapper, boostDecFloat16.str().c_str(), &opaqueDecFloat16);
 			return opaqueDecFloat16;
@@ -414,7 +414,7 @@ namespace fbcpp::impl
 
 		OpaqueDecFloat34 boostDecFloat34ToOpaqueDecFloat34(const BoostDecFloat34& boostDecFloat34)
 		{
-			const auto decFloat34Util = client.getDecFloat34Util(statusWrapper);
+			const auto decFloat34Util = client->getDecFloat34Util(statusWrapper);
 			OpaqueDecFloat34 opaqueDecFloat34;
 			decFloat34Util->fromString(statusWrapper, boostDecFloat34.str().c_str(), &opaqueDecFloat34);
 			return opaqueDecFloat34;
@@ -573,7 +573,7 @@ namespace fbcpp::impl
 		}
 
 	private:
-		Client& client;
+		Client* client;
 		StatusWrapper* statusWrapper;
 	};
 }  // namespace fbcpp::impl
diff --git a/src/fb-cpp/Statement.cpp b/src/fb-cpp/Statement.cpp
index a42a5b1..700e74b 100644
--- a/src/fb-cpp/Statement.cpp
+++ b/src/fb-cpp/Statement.cpp
@@ -33,7 +33,7 @@ using namespace fbcpp::impl;
 
 Statement::Statement(
 	Attachment& attachment, Transaction& transaction, std::string_view sql, const StatementOptions& options)
-	: attachment{attachment},
+	: attachment{&attachment},
 	  status{attachment.getClient().newStatus()},
 	  statusWrapper{attachment.getClient(), status.get()},
 	  calendarConverter{attachment.getClient(), &statusWrapper},
diff --git a/src/fb-cpp/Statement.h b/src/fb-cpp/Statement.h
index 3d1e30c..e6c37be 100644
--- a/src/fb-cpp/Statement.h
+++ b/src/fb-cpp/Statement.h
@@ -272,7 +272,36 @@ namespace fbcpp
 		{
 		}
 
-		Statement& operator=(Statement&&) = delete;
+		///
+		/// @brief Transfers ownership of another prepared statement into this one.
+		///
+		/// The old handles are released via `FbRef::operator=(FbRef&&)`.
+		/// After the assignment, `this` is valid (with `o`'s state) and `o` is invalid.
+		///
+		Statement& operator=(Statement&& o) noexcept
+		{
+			if (this != &o)
+			{
+				attachment = o.attachment;
+				status = std::move(o.status);
+				statusWrapper = std::move(o.statusWrapper);
+				calendarConverter = std::move(o.calendarConverter);
+				numericConverter = std::move(o.numericConverter);
+				statementHandle = std::move(o.statementHandle);
+				resultSetHandle = std::move(o.resultSetHandle);
+				inMetadata = std::move(o.inMetadata);
+				inDescriptors = std::move(o.inDescriptors);
+				inMessage = std::move(o.inMessage);
+				outMetadata = std::move(o.outMetadata);
+				outDescriptors = std::move(o.outDescriptors);
+				outMessage = std::move(o.outMessage);
+				type = o.type;
+				cursorFlags = o.cursorFlags;
+			}
+
+			return *this;
+		}
+
 		Statement(const Statement&) = delete;
 		Statement& operator=(const Statement&) = delete;
 
@@ -1090,7 +1119,7 @@ namespace fbcpp
 
 			assert(isValid());
 
-			auto& client = attachment.getClient();
+			auto& client = attachment->getClient();
 			const auto value = optValue.value();
 			const auto& descriptor = getInDescriptor(index);
 			const auto message = inMessage.data();
@@ -2759,7 +2788,7 @@ namespace fbcpp
 		}
 
 	private:
-		Attachment& attachment;
+		Attachment* attachment;
 		FbUniquePtr<Firebird::IStatus> status;
 		impl::StatusWrapper statusWrapper;
 		impl::CalendarConverter calendarConverter;
diff --git a/src/test/Attachment.cpp b/src/test/Attachment.cpp
index cec54a1..350c16f 100644
--- a/src/test/Attachment.cpp
+++ b/src/test/Attachment.cpp
@@ -71,6 +71,31 @@ BOOST_AUTO_TEST_CASE(isNotValidAfterMove)
 	BOOST_CHECK_EQUAL(attachment1.isValid(), false);
 }
 
+BOOST_AUTO_TEST_CASE(moveAssignmentTransfersOwnership)
+{
+	const auto database1 = getTempFile("Attachment-moveAssign-1.fdb");
+	const auto database2 = getTempFile("Attachment-moveAssign-2.fdb");
+
+	Attachment attachment1{CLIENT, database1, AttachmentOptions().setCreateDatabase(true)};
+	Attachment attachment2{CLIENT, database2, AttachmentOptions().setCreateDatabase(true)};
+	BOOST_CHECK(attachment1.isValid());
+	BOOST_CHECK(attachment2.isValid());
+
+	// Move-assign attachment2 into attachment1.
+	// attachment1's old connection is disconnected; attachment2 becomes invalid.
+	attachment1 = std::move(attachment2);
+	BOOST_CHECK(attachment1.isValid());
+	BOOST_CHECK(!attachment2.isValid());
+
+	// The moved-to attachment can still operate on the database.
+	attachment1.dropDatabase();
+	BOOST_CHECK(!attachment1.isValid());
+
+	// Clean up the first database (its connection was disconnected by the move).
+	Attachment cleanup{CLIENT, database1};
+	cleanup.dropDatabase();
+}
+
 BOOST_AUTO_TEST_CASE(isNotValidAfterDisconnect)
 {
 	const auto database = getTempFile("Attachment-isNotValidAfterDisconnect.fdb");
diff --git a/src/test/Statement.cpp b/src/test/Statement.cpp
index b802065..4eef52a 100644
--- a/src/test/Statement.cpp
+++ b/src/test/Statement.cpp
@@ -78,6 +78,54 @@ BOOST_AUTO_TEST_CASE(isNotValidAfterMove)
 	BOOST_CHECK_EQUAL(stmt2.isValid(), true);
 }
 
+BOOST_AUTO_TEST_CASE(moveAssignmentTransfersOwnership)
+{
+	const auto database = getTempFile("Statement-moveAssignmentTransfersOwnership.fdb");
+
+	Attachment attachment{CLIENT, database, AttachmentOptions().setCreateDatabase(true)};
+	FbDropDatabase attachmentDrop{attachment};
+
+	Transaction transaction{attachment};
+	Statement stmt1{attachment, transaction, "select 1 from rdb$database"};
+	Statement stmt2{attachment, transaction, "select 2 from rdb$database"};
+	BOOST_CHECK(stmt1.isValid());
+	BOOST_CHECK(stmt2.isValid());
+
+	// Move-assign stmt2 into stmt1.
+	// stmt1's old handle is freed; stmt2 becomes invalid.
+	stmt1 = std::move(stmt2);
+	BOOST_CHECK(stmt1.isValid());
+	BOOST_CHECK(!stmt2.isValid());
+
+	// The moved-to statement can still execute.
+	BOOST_CHECK(stmt1.execute(transaction));
+	BOOST_CHECK_EQUAL(stmt1.getInt32(0).value(), 2);
+}
+
+BOOST_AUTO_TEST_CASE(moveAssignmentToMovedFromStatement)
+{
+	const auto database = getTempFile("Statement-moveAssignmentToMovedFrom.fdb");
+
+	Attachment attachment{CLIENT, database, AttachmentOptions().setCreateDatabase(true)};
+	FbDropDatabase attachmentDrop{attachment};
+
+	Transaction transaction{attachment};
+	Statement stmt1{attachment, transaction, "select 1 from rdb$database"};
+	Statement stmt2{attachment, transaction, "select 2 from rdb$database"};
+
+	// Move-construct stmt3 from stmt1 (leaves stmt1 invalid).
+	Statement stmt3{std::move(stmt1)};
+	BOOST_CHECK(!stmt1.isValid());
+
+	// Move-assign into the moved-from stmt1.
+	stmt1 = std::move(stmt2);
+	BOOST_CHECK(stmt1.isValid());
+	BOOST_CHECK(!stmt2.isValid());
+
+	BOOST_CHECK(stmt1.execute(transaction));
+	BOOST_CHECK_EQUAL(stmt1.getInt32(0).value(), 2);
+}
+
 BOOST_AUTO_TEST_CASE(freeReleasesHandle)
 {
 	const auto database = getTempFile("Statement-freeReleasesHandle.fdb");