diff --git a/colour.cpp b/colour.cpp
index 1c5a368e..cbabf41f 100644
--- a/colour.cpp
+++ b/colour.cpp
@@ -382,12 +382,12 @@ namespace util {
 template <size_t S, typename T>
 std::ostream&
 util::operator<< (std::ostream &os, util::colour<S,T> c) {
-    os << "colour(";
+    os << "[";
     std::transform (std::cbegin (c),
                     std::cend   (c),
                     infix_iterator<stream::numeric<T>> (os, ", "),
                     stream::to_numeric<T>);
-    os << ")";
+    os << "]";
 
     return os;
 }
diff --git a/coord/iostream.hpp b/coord/iostream.hpp
index d5254a3e..3b6386fb 100644
--- a/coord/iostream.hpp
+++ b/coord/iostream.hpp
@@ -21,6 +21,7 @@
 #include "../stream.hpp"
 
 #include <ostream>
+#include <algorithm>
 
 namespace util {
     template <
diff --git a/extent.cpp b/extent.cpp
index 3047dddc..6f64e4bb 100644
--- a/extent.cpp
+++ b/extent.cpp
@@ -232,25 +232,9 @@ template bool util::debug::valid (const extent<2,uint32_t>&);
 template bool util::debug::valid (const extent<2,uint64_t>&);
 
 
-///////////////////////////////////////////////////////////////////////////////
-template <size_t S, typename T>
-std::ostream&
-util::operator<< (std::ostream &os, extent<S,T> e)
-{
-    os << "[";
-    std::transform (std::cbegin (e.data),
-                    std::cend   (e.data),
-                    infix_iterator<stream::numeric<T>> (os, ", "),
-                    stream::to_numeric<T>);
-    os << "]";
-    return os;
-}
-
-
 //-----------------------------------------------------------------------------
-#define INSTANTIATE_S_T(S,T)                                        \
-template struct util::extent<S,T>;                                        \
-template std::ostream& util::operator<< (std::ostream&, extent<S,T>);
+#define INSTANTIATE_S_T(S,T)        \
+template struct util::extent<S,T>;
 
 #define INSTANTIATE(T)      \
 INSTANTIATE_S_T(1,T)        \
diff --git a/extent.hpp b/extent.hpp
index 016545d8..ae220166 100644
--- a/extent.hpp
+++ b/extent.hpp
@@ -21,8 +21,6 @@
 #include "vector.hpp"
 #include "point.hpp"
 
-#include <iostream>
-
 
 namespace util {
     /**
@@ -107,9 +105,6 @@ namespace util {
     using extent_range2i = extent_range2<typename extent2i::value_type>;
 
     using extent_range3u = extent_range2<typename extent3u::value_type>;
-
-    template <size_t S, typename T>
-    std::ostream& operator<< (std::ostream&, util::extent<S,T>);
 }
 
 
diff --git a/fourcc.cpp b/fourcc.cpp
index f0e3778a..8254e0e0 100644
--- a/fourcc.cpp
+++ b/fourcc.cpp
@@ -17,12 +17,11 @@
 #include "fourcc.hpp"
 
 using util::fourcc;
-using std::ostream;
-
 
 static_assert (sizeof(fourcc) == 4, "fourcc must be a 4 byte POD");
 
 
+///////////////////////////////////////////////////////////////////////////////
 fourcc
 fourcc::from_chars (uint8_t a, uint8_t b, uint8_t c, uint8_t d) {
     fourcc lhs;
@@ -36,6 +35,7 @@ fourcc::from_chars (uint8_t a, uint8_t b, uint8_t c, uint8_t d) {
 }
 
 
+//-----------------------------------------------------------------------------
 fourcc
 fourcc::from_string (const char data[4]) {
     fourcc lhs;
@@ -49,6 +49,7 @@ fourcc::from_string (const char data[4]) {
 }
 
 
+///////////////////////////////////////////////////////////////////////////////
 bool
 fourcc::operator== (const char rhs[4]) const {
     return data[0] == rhs[0] &&
@@ -58,6 +59,7 @@ fourcc::operator== (const char rhs[4]) const {
 }
 
 
+///////////////////////////////////////////////////////////////////////////////
 fourcc::operator uint32_t (void) const {
     return static_cast<uint32_t> (data[0] << 24U |
                                   data[1] << 16U |
@@ -66,9 +68,9 @@ fourcc::operator uint32_t (void) const {
 }
 
 
-ostream&
-operator<< (ostream &os, fourcc f) {
+///////////////////////////////////////////////////////////////////////////////
+std::ostream&
+util::operator<< (std::ostream &os, fourcc f) {
     os << f.data[0] << f.data[1] << f.data[2] << f.data[3];
     return os;
 }
-
diff --git a/fourcc.hpp b/fourcc.hpp
index 8f26cbbd..abcec3ad 100644
--- a/fourcc.hpp
+++ b/fourcc.hpp
@@ -17,7 +17,7 @@
 #ifndef __UTIL_FOURCC_HPP
 #define __UTIL_FOURCC_HPP
 
-#include <iostream>
+#include <ostream>
 #include <cstdint>
 
 namespace util {
@@ -30,8 +30,9 @@ namespace util {
         bool operator== (const char[4]) const;
         operator uint32_t (void) const;
     };
+
+    std::ostream& operator<< (std::ostream&, util::fourcc);
 }
 
-std::ostream& operator<< (std::ostream&, util::fourcc);
 
 #endif
diff --git a/guid.hpp b/guid.hpp
index 9993a706..c96cfbe5 100644
--- a/guid.hpp
+++ b/guid.hpp
@@ -18,7 +18,8 @@
 #define __UTIL_GUID_HPP
 
 #include <cstdint>
-#include <iostream>
+#include <ostream>
+#include <istream>
 
 class guid {
     public:
diff --git a/quaternion.hpp b/quaternion.hpp
index e6d77502..239d4f48 100644
--- a/quaternion.hpp
+++ b/quaternion.hpp
@@ -20,7 +20,7 @@
 #include "vector.hpp"
 #include "matrix.hpp"
 
-#include <iostream>
+#include <ostream>
 
 
 namespace util {
@@ -82,7 +82,8 @@ namespace util {
     typedef quaternion<float> quaternionf;
 
     template <typename T>
-    std::ostream& operator<< (std::ostream&, quaternion<T>);
+    std::ostream&
+    operator<< (std::ostream&, quaternion<T>);
 }
 
 
diff --git a/region.cpp b/region.cpp
index 26c6404b..72a5185a 100644
--- a/region.cpp
+++ b/region.cpp
@@ -365,8 +365,7 @@ util::region<S,T>::UNIT (util::point<S,T>{0}, util::extent<S,T>{1});
 template <size_t S, typename T>
 std::ostream&
 util::operator<< (std::ostream &os, const util::region<S,T> &rhs) {
-    os << "region(" << rhs.p << ", " << rhs.e << ")";
-    return os;
+    return os << "{position: " << rhs.p << ", extent: " << rhs.e << "}";
 }
 
 
diff --git a/region.hpp b/region.hpp
index 12792f34..12e39c0b 100644
--- a/region.hpp
+++ b/region.hpp
@@ -23,6 +23,8 @@
 #include "vector.hpp"
 #include "types/traits.hpp"
 
+#include <ostream>
+
 namespace util {
     /**
      * A two-dimensional rectangle, with size and position.
diff --git a/vector.cpp b/vector.cpp
index a74674c1..d7352b95 100644
--- a/vector.cpp
+++ b/vector.cpp
@@ -248,21 +248,6 @@ util::vector<S,T>::sanity (void) const
 
 
 ///////////////////////////////////////////////////////////////////////////////
-// ostream
-
-template <size_t S, typename T>
-std::ostream&
-util::operator<< (std::ostream &os, util::vector<S,T> v)
-{
-    os << "vec" << S << "(" << v.data[0];
-    for (size_t i = 1; i < S; ++i)
-        os << ", " << v.data[i];
-    os << ")";
-    return os;
-}
-
-
-//-----------------------------------------------------------------------------
 template <size_t S, typename T>
 const json::tree::node&
 util::operator>> (const json::tree::node &node, util::vector<S,T> &v)
@@ -284,7 +269,6 @@ util::operator>> (const json::tree::node &node, util::vector<S,T> &v)
 //-----------------------------------------------------------------------------
 #define INSTANTIATE_S_T(S,T)                                                    \
 template struct util::vector<S,T>;                                              \
-template std::ostream& util::operator<< (std::ostream&, util::vector<S,T> v);   \
 template const json::tree::node& util::operator>> (const json::tree::node&, util::vector<S,T>&);
 
 
diff --git a/vector.hpp b/vector.hpp
index c7f6cf0d..a93baec8 100644
--- a/vector.hpp
+++ b/vector.hpp
@@ -21,7 +21,6 @@
 #include "coord.hpp"
 
 #include <array>
-#include <iostream>
 #include <initializer_list>
 
 namespace util {
@@ -67,8 +66,6 @@ namespace util {
     template <typename T> vector<3,T> from_euler (vector<2,T>);
 
     // output and serialisation operators
-    template <size_t S, typename T> std::ostream& operator<< (std::ostream&, vector<S,T>);
-
     template <size_t S, typename T>
     const json::tree::node& operator>> (const json::tree::node&, vector<S,T>&);