diff --git a/CMakeLists.txt b/CMakeLists.txt
index dd67fb5..ed8a606 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -69,6 +69,8 @@ list (APPEND sources
     instance.hpp
     image.cpp
     image.hpp
+    ostream.cpp
+    ostream.hpp
     physical_device.cpp
     physical_device.hpp
     pipeline.cpp
diff --git a/ostream.cpp b/ostream.cpp
new file mode 100644
index 0000000..0df127c
--- /dev/null
+++ b/ostream.cpp
@@ -0,0 +1,136 @@
+/*
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ *
+ * Copyright:
+ *      2017, Danny Robson <danny@nerdcruft.net>
+ */
+
+#include "./ostream.hpp"
+
+#include "./instance.hpp"
+#include "./physical_device.hpp"
+
+#include <iomanip>
+#include <cruft/util/iterator.hpp>
+
+
+///////////////////////////////////////////////////////////////////////////////
+static
+std::ostream&
+write_version (std::ostream &os, uint32_t version)
+{
+    static constexpr uint32_t MAJOR_BITS = 10;
+    static constexpr uint32_t MINOR_BITS = 10;
+    static constexpr uint32_t PATCH_BITS = 12;
+    static_assert (MAJOR_BITS + MINOR_BITS + PATCH_BITS == sizeof (version) * 8);
+
+    uint32_t major, minor, patch;
+
+    patch = version & ((1 << PATCH_BITS) - 1); version >>= PATCH_BITS;
+    minor = version & ((1 << MINOR_BITS) - 1); version >>= MINOR_BITS;
+    major = version & ((1 << MAJOR_BITS) - 1); version >>= MAJOR_BITS;
+
+    return os << +major << '.' << +minor << '.' << +patch;
+}
+
+
+///////////////////////////////////////////////////////////////////////////////
+std::ostream&
+cruft::vk::operator<< (std::ostream &os, const instance &i)
+{
+    os << "{ extensions: [ ";
+
+    const auto &extensions = i.extensions ();
+    std::copy (std::cbegin (extensions),
+               std::cend   (extensions),
+               util::infix_iterator<std::string> (os, ", "));
+
+    return os << " ] }";
+}
+
+
+///////////////////////////////////////////////////////////////////////////////
+std::ostream&
+operator<< (std::ostream &os, VkPhysicalDeviceType t)
+{
+    switch (t) {
+    case VK_PHYSICAL_DEVICE_TYPE_OTHER:             return os << "other";
+    case VK_PHYSICAL_DEVICE_TYPE_INTEGRATED_GPU:    return os << "integrated-gpu";
+    case VK_PHYSICAL_DEVICE_TYPE_DISCRETE_GPU:      return os << "discrete-gpu";
+    case VK_PHYSICAL_DEVICE_TYPE_VIRTUAL_GPU:       return os << "virtual-gpu";
+    case VK_PHYSICAL_DEVICE_TYPE_CPU:               return os << "cpu";
+    }
+
+    return os << "unknown-" << +static_cast<std::underlying_type_t<decltype(t)>> (t);
+}
+
+
+//-----------------------------------------------------------------------------
+std::ostream&
+operator<< (std::ostream &os, const VkPhysicalDeviceLimits &l)
+{
+    return os
+        << "{ max_image: [ " << l.maxImageDimension1D
+                     << ", " << l.maxImageDimension2D
+                     << ", " << l.maxImageDimension3D
+                     << " ]"
+        << " }";
+}
+
+
+//-----------------------------------------------------------------------------
+std::ostream&
+operator<< (std::ostream &os, const VkPhysicalDeviceProperties &p)
+{
+    os << "{ api: ";    write_version (os, p.apiVersion);
+    os << ", driver: "; write_version (os, p.driverVersion);
+    os << ", vendor: 0x" << std::hex << std::setw (4) << std::setfill ('0') << p.vendorID << std::dec;
+    os << ", device: 0x" << std::hex << std::setw (4) << std::setfill ('0') << p.deviceID << std::dec;
+    os << ", name: '"  << p.deviceName << "'";
+    os << ", type: "   << p.deviceType;
+    os << ", limits: " << p.limits;
+    os << " }";
+
+    return os;
+}
+
+
+//-----------------------------------------------------------------------------
+std::ostream&
+operator<< (std::ostream &os, const VkPhysicalDeviceFeatures &f)
+{
+    os << "[ ";
+    if (f.geometryShader) os << "GEOMETRY_SHADER ";
+    return os << "]";
+}
+
+
+///////////////////////////////////////////////////////////////////////////////
+std::ostream&
+cruft::vk::operator<< (std::ostream &os, const physical_device &d)
+{
+    os << "physical_device { ";
+
+    os << "extensions: [ ";
+    const auto &extensions = d.extensions ();
+    std::copy (std::cbegin (extensions),
+               std::cend   (extensions),
+               util::infix_iterator<std::string> (os, ", "));
+    os << " ], ";
+
+    os << " properties: " << d.properties ()
+       << ", features: " << d.features ()
+       << " }";
+
+    return os;
+}
\ No newline at end of file
diff --git a/ostream.hpp b/ostream.hpp
new file mode 100644
index 0000000..db5cf15
--- /dev/null
+++ b/ostream.hpp
@@ -0,0 +1,38 @@
+/*
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ *
+ * Copyright:
+ *      2017, Danny Robson <danny@nerdcruft.net>
+ */
+
+#ifndef CRUFT_VK_OSTREAM_HPP
+#define CRUFT_VK_OSTREAM_HPP
+
+#include "./fwd.hpp"
+#include "./vk.hpp"
+
+#include <cruft/util/preprocessor.hpp>
+
+#include <ostream>
+
+std::ostream& operator<< (std::ostream&, VkPhysicalDeviceType);
+std::ostream& operator<< (std::ostream&, const VkPhysicalDeviceLimits&);
+std::ostream& operator<< (std::ostream&, const VkPhysicalDeviceProperties&);
+
+namespace cruft::vk {
+#define CRUFT_VK_OSTREAM(T) std::ostream& operator<< (std::ostream&, const cruft::vk::T&);
+VK_TYPE_MAP (CRUFT_VK_OSTREAM)
+#undef CRUFT_VK_OSTREAM
+}
+
+#endif