diff --git a/scripts/tests.sh b/scripts/tests.sh
index 27cad6e32153..553454583511 100755
--- a/scripts/tests.sh
+++ b/scripts/tests.sh
@@ -190,18 +190,33 @@ for optimize in "" "--optimize"
 do
   for vm in $EVM_VERSIONS
   do
-    printTask "--> Running tests using "$optimize" --evm-version "$vm"..."
-    log=""
-    if [ -n "$log_directory" ]
+    FORCE_ABIV2_RUNS="no"
+    if [[ "$vm" == "constantinople" ]]
     then
-      if [ -n "$optimize" ]
-      then
-        log=--logger=JUNIT,test_suite,$log_directory/opt_$vm.xml $testargs
-      else
-        log=--logger=JUNIT,test_suite,$log_directory/noopt_$vm.xml $testargs_no_opt
-      fi
+      FORCE_ABIV2_RUNS="no yes" # run both in constantinople
     fi
-    "$REPO_ROOT"/build/test/soltest $progress $log -- --testpath "$REPO_ROOT"/test "$optimize" --evm-version "$vm" $SMT_FLAGS $IPC_FLAGS  --ipcpath "${WORKDIR}/geth.ipc"
+    for abiv2 in $FORCE_ABIV2_RUNS
+    do
+        force_abiv2_flag=""
+        if [[ "$abiv2" == "yes" ]]
+        then
+            force_abiv2_flag="--abiencoderv2"
+        fi
+        printTask "--> Running tests using "$optimize" --evm-version "$vm" $force_abiv2_flag..."
+
+        log=""
+        if [ -n "$log_directory" ]
+        then
+        if [ -n "$optimize" ]
+        then
+            log=--logger=JUNIT,test_suite,$log_directory/opt_$vm.xml $testargs
+        else
+            log=--logger=JUNIT,test_suite,$log_directory/noopt_$vm.xml $testargs_no_opt
+        fi
+        fi
+
+        "$REPO_ROOT"/build/test/soltest $progress $log -- --testpath "$REPO_ROOT"/test "$optimize" --evm-version "$vm" $SMT_FLAGS $IPC_FLAGS $force_abiv2_flag --ipcpath "${WORKDIR}/geth.ipc"
+    done
   done
 done
 
diff --git a/test/Options.cpp b/test/Options.cpp
index 9f0d6752e3e8..8389d853b221 100644
--- a/test/Options.cpp
+++ b/test/Options.cpp
@@ -55,6 +55,8 @@ Options::Options()
 		}
 		else if (string(suite.argv[i]) == "--optimize")
 			optimize = true;
+		else if (string(suite.argv[i]) == "--abiencoderv2")
+			useABIEncoderV2 = true;
 		else if (string(suite.argv[i]) == "--evm-version")
 		{
 			evmVersionString = i + 1 < suite.argc ? suite.argv[i + 1] : "INVALID";
diff --git a/test/Options.h b/test/Options.h
index af6f06ee4247..f510aade0f5f 100644
--- a/test/Options.h
+++ b/test/Options.h
@@ -41,6 +41,7 @@ struct Options: boost::noncopyable
 	bool optimize = false;
 	bool disableIPC = false;
 	bool disableSMT = false;
+	bool useABIEncoderV2 = false;
 
 	void validate() const;
 	solidity::EVMVersion evmVersion() const;
diff --git a/test/libsolidity/ABIDecoderTests.cpp b/test/libsolidity/ABIDecoderTests.cpp
index 291ed15aade9..ce6afcf355c8 100644
--- a/test/libsolidity/ABIDecoderTests.cpp
+++ b/test/libsolidity/ABIDecoderTests.cpp
@@ -86,7 +86,7 @@ BOOST_AUTO_TEST_CASE(enums)
 			}
 		}
 	)";
-	bool newDecoder = false;
+	bool newDecoder = dev::test::Options::get().useABIEncoderV2;
 	BOTH_ENCODERS(
 		compileAndRun(sourceCode);
 		ABI_CHECK(callContractFunction("f(uint8)", 0), encodeArgs(u256(0)));
diff --git a/test/libsolidity/ABIEncoderTests.cpp b/test/libsolidity/ABIEncoderTests.cpp
index f56b8ad1f580..a8f175543d4e 100644
--- a/test/libsolidity/ABIEncoderTests.cpp
+++ b/test/libsolidity/ABIEncoderTests.cpp
@@ -164,10 +164,13 @@ BOOST_AUTO_TEST_CASE(memory_array_one_dim)
 		}
 	)";
 
-	compileAndRun(sourceCode);
-	callContractFunction("f()");
-	// The old encoder does not clean array elements.
-	REQUIRE_LOG_DATA(encodeArgs(10, 0x60, 11, 3, u256("0xfffffffe"), u256("0xffffffff"), u256("0x100000000")));
+	if (!dev::test::Options::get().useABIEncoderV2)
+	{
+		compileAndRun(sourceCode);
+		callContractFunction("f()");
+		// The old encoder does not clean array elements.
+		REQUIRE_LOG_DATA(encodeArgs(10, 0x60, 11, 3, u256("0xfffffffe"), u256("0xffffffff"), u256("0x100000000")));
+	}
 
 	compileAndRun(NewEncoderPragma + sourceCode);
 	callContractFunction("f()");
diff --git a/test/libsolidity/GasCosts.cpp b/test/libsolidity/GasCosts.cpp
index c7da3ca04037..44fd5bf77f18 100644
--- a/test/libsolidity/GasCosts.cpp
+++ b/test/libsolidity/GasCosts.cpp
@@ -70,6 +70,9 @@ BOOST_AUTO_TEST_CASE(string_storage)
 
 	if (Options::get().evmVersion() <= EVMVersion::byzantium())
 		CHECK_GAS(134435, 130591, 100);
+	// This is only correct on >=Constantinople.
+	else if (Options::get().useABIEncoderV2)
+		CHECK_GAS(151819, 142753, 100);
 	else
 		CHECK_GAS(127225, 124873, 100);
 	if (Options::get().evmVersion() >= EVMVersion::byzantium())
@@ -77,6 +80,9 @@ BOOST_AUTO_TEST_CASE(string_storage)
 		callContractFunction("f()");
 		if (Options::get().evmVersion() == EVMVersion::byzantium())
 			CHECK_GAS(21551, 21526, 20);
+		// This is only correct on >=Constantinople.
+		else if (Options::get().useABIEncoderV2)
+			CHECK_GAS(21713, 21635, 20);
 		else
 			CHECK_GAS(21546, 21526, 20);
 	}
diff --git a/test/libsolidity/GasMeter.cpp b/test/libsolidity/GasMeter.cpp
index d765d440bb7a..54d3c247c09c 100644
--- a/test/libsolidity/GasMeter.cpp
+++ b/test/libsolidity/GasMeter.cpp
@@ -73,9 +73,14 @@ class GasMeterTestFramework: public SolidityExecutionFramework
 		// costs for transaction
 		gas += gasForTransaction(m_compiler.object(m_compiler.lastContractName()).bytecode, true);
 
-		BOOST_REQUIRE(!gas.isInfinite);
-		BOOST_CHECK_LE(m_gasUsed, gas.value);
-		BOOST_CHECK_LE(gas.value - _tolerance, m_gasUsed);
+		// Skip the tests when we force ABIEncoderV2.
+		// TODO: We should enable this again once the yul optimizer is activated.
+		if (!dev::test::Options::get().useABIEncoderV2)
+		{
+			BOOST_REQUIRE(!gas.isInfinite);
+			BOOST_CHECK_LE(m_gasUsed, gas.value);
+			BOOST_CHECK_LE(gas.value - _tolerance, m_gasUsed);
+		}
 	}
 
 	/// Compares the gas computed by PathGasMeter for the given signature (but unknown arguments)
@@ -97,9 +102,14 @@ class GasMeterTestFramework: public SolidityExecutionFramework
 			*m_compiler.runtimeAssemblyItems(m_compiler.lastContractName()),
 			_sig
 		);
-		BOOST_REQUIRE(!gas.isInfinite);
-		BOOST_CHECK_LE(m_gasUsed, gas.value);
-		BOOST_CHECK_LE(gas.value - _tolerance, m_gasUsed);
+		// Skip the tests when we force ABIEncoderV2.
+		// TODO: We should enable this again once the yul optimizer is activated.
+		if (!dev::test::Options::get().useABIEncoderV2)
+		{
+			BOOST_REQUIRE(!gas.isInfinite);
+			BOOST_CHECK_LE(m_gasUsed, gas.value);
+			BOOST_CHECK_LE(gas.value - _tolerance, m_gasUsed);
+		}
 	}
 
 	static GasMeter::GasConsumption gasForTransaction(bytes const& _data, bool _isCreation)
diff --git a/test/libsolidity/SolidityEndToEndTest.cpp b/test/libsolidity/SolidityEndToEndTest.cpp
index c540ef320f43..ee3cc626b33c 100644
--- a/test/libsolidity/SolidityEndToEndTest.cpp
+++ b/test/libsolidity/SolidityEndToEndTest.cpp
@@ -14317,12 +14317,17 @@ BOOST_AUTO_TEST_CASE(abi_encode_empty_string)
 			}
 		}
 	)";
+
 	compileAndRun(sourceCode, 0, "C");
-	ABI_CHECK(callContractFunction("f()"), encodeArgs(
-		0x40, 0xc0,
-		0x60, 0x20, 0x00, 0x00,
-		0x00
-	));
+	if (!dev::test::Options::get().useABIEncoderV2)
+	{
+		// ABI Encoder V2 has slightly different padding, tested below.
+		ABI_CHECK(callContractFunction("f()"), encodeArgs(
+			0x40, 0xc0,
+			0x60, 0x20, 0x00, 0x00,
+			0x00
+		));
+	}
 }
 
 BOOST_AUTO_TEST_CASE(abi_encode_empty_string_v2)
diff --git a/test/libsolidity/SolidityExecutionFramework.h b/test/libsolidity/SolidityExecutionFramework.h
index bda1c2486c80..37adbdf4e457 100644
--- a/test/libsolidity/SolidityExecutionFramework.h
+++ b/test/libsolidity/SolidityExecutionFramework.h
@@ -65,7 +65,10 @@ class SolidityExecutionFramework: public dev::test::ExecutionFramework
 	)
 	{
 		// Silence compiler version warning
-		std::string sourceCode = "pragma solidity >=0.0;\n" + _sourceCode;
+		std::string sourceCode = "pragma solidity >=0.0;\n";
+		if (dev::test::Options::get().useABIEncoderV2 && _sourceCode.find("pragma experimental ABIEncoderV2;") == std::string::npos)
+			sourceCode += "pragma experimental ABIEncoderV2;\n";
+		sourceCode += _sourceCode;
 		m_compiler.reset(false);
 		m_compiler.addSource("", sourceCode);
 		m_compiler.setLibraries(_libraryAddresses);