diff --git a/README.md b/README.md
index aeaf61c..a345c56 100644
--- a/README.md
+++ b/README.md
@@ -248,6 +248,10 @@ public:
         const row_type& row1,
         const row_type& row2);
 
+    constexpr mat_base(
+        const mat_base<T, 2>& m,
+        const vec_base<T, 2>& v);
+
     constexpr explicit mat_base(const mat_base<T, 2>& other);
     constexpr explicit mat_base(const mat_base<T, 4>& other);
 };
@@ -279,6 +283,10 @@ public:
         const row_type& row2,
         const row_type& row3);
 
+    constexpr mat_base(
+        const mat_base<T, 3>& m,
+        const vec_base<T, 3>& v);
+
     constexpr explicit mat_base(const mat_base<T, 2>& other);
     constexpr explicit mat_base(const mat_base<T, 3>& other);
 };
diff --git a/headers/vmath.hpp/vmath_mat.hpp b/headers/vmath.hpp/vmath_mat.hpp
index 65d8b4c..7111014 100644
--- a/headers/vmath.hpp/vmath_mat.hpp
+++ b/headers/vmath.hpp/vmath_mat.hpp
@@ -99,6 +99,14 @@ namespace vmath_hpp::detail
             const row_type& row2)
         : rows{row0, row1, row2} {}
 
+        constexpr mat_base(
+            const mat_base<T, 2>& m,
+            const vec_base<T, 2>& v)
+        : rows{
+            row_type{m.rows[0], 0},
+            row_type{m.rows[1], 0},
+            row_type{v, 1}} {}
+
         constexpr explicit mat_base(
             const mat_base<T, 2>& other)
         : rows{
@@ -158,6 +166,15 @@ namespace vmath_hpp::detail
             const row_type& row3)
         : rows{row0, row1, row2, row3} {}
 
+        constexpr mat_base(
+            const mat_base<T, 3>& m,
+            const vec_base<T, 3>& v)
+        : rows{
+            row_type{m.rows[0], 0},
+            row_type{m.rows[1], 0},
+            row_type{m.rows[2], 0},
+            row_type{v, 1}} {}
+
         constexpr explicit mat_base(
             const mat_base<T, 2>& other)
         : rows{
@@ -281,6 +298,9 @@ namespace vmath_hpp
     template < typename T >
     mat(const vec<T, 3>&, const vec<T, 3>&, const vec<T, 3>&) -> mat<T, 3>;
 
+    template < typename T >
+    mat(const mat<T, 2>&, const vec<T, 2>&) -> mat<T, 3>;
+
     template < typename T >
     mat(std::initializer_list<T>, std::initializer_list<T>, std::initializer_list<T>) -> mat<T, 3>;
 
@@ -292,6 +312,9 @@ namespace vmath_hpp
     template < typename T >
     mat(const vec<T, 4>&, const vec<T, 4>&, const vec<T, 4>&, const vec<T, 4>&) -> mat<T, 4>;
 
+    template < typename T >
+    mat(const mat<T, 3>&, const vec<T, 3>&) -> mat<T, 4>;
+
     template < typename T >
     mat(std::initializer_list<T>, std::initializer_list<T>, std::initializer_list<T>, std::initializer_list<T>) -> mat<T, 4>;
 
diff --git a/untests/vmath_mat_tests.cpp b/untests/vmath_mat_tests.cpp
index 97688d1..fed8be3 100644
--- a/untests/vmath_mat_tests.cpp
+++ b/untests/vmath_mat_tests.cpp
@@ -32,10 +32,12 @@ TEST_CASE("vmath/mat") {
         STATIC_REQUIRE(mat{1,2,3,4,5,6,7,8,9}.size == 3);
         STATIC_REQUIRE(mat{{1,2,3},{4,5,6},{7,8,9}}.size == 3);
         STATIC_REQUIRE(mat{vec{1,2,3},vec{4,5,6},vec{7,8,9}}.size == 3);
+        STATIC_REQUIRE(mat{mat{1,2,3,4},vec{5,6}}.size == 3);
 
         STATIC_REQUIRE(mat{1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16}.size == 4);
         STATIC_REQUIRE(mat{{1,2,3,4},{5,6,7,8},{9,10,11,12},{13,14,15,16}}.size == 4);
         STATIC_REQUIRE(mat{vec{1,2,3,4},vec{5,6,7,8},vec{9,10,11,12},vec{13,14,15,16}}.size == 4);
+        STATIC_REQUIRE(mat{mat{1,2,3,4,5,6,7,8,9},vec{5,6,7}}.size == 4);
     }
 
     SUBCASE("ctors") {
@@ -74,6 +76,7 @@ TEST_CASE("vmath/mat") {
             STATIC_REQUIRE(int3x3(int3{2,3,4}) == int3x3(2,0,0,0,3,0,0,0,4));
             STATIC_REQUIRE(int3x3(1,2,3,4,5,6,7,8,9) == int3x3(1,2,3,4,5,6,7,8,9));
             STATIC_REQUIRE(int3x3({1,2,3},{4,5,6},{7,8,9}) == int3x3(1,2,3,4,5,6,7,8,9));
+            STATIC_REQUIRE(int3x3(int2x2({1,2},{3,4}),int2{5,6}) == int3x3(1,2,0,3,4,0,5,6,1));
             STATIC_REQUIRE(int3x3(int3x3({1,2,3},{4,5,6},{7,8,9})) == int3x3(1,2,3,4,5,6,7,8,9));
             STATIC_REQUIRE(int3x3(int2x2({1,2},{3,4})) == int3x3(1,2,0,3,4,0,0,0,1));
             STATIC_REQUIRE(int3x3(int4x4({1,2,3,4},{5,6,7,8},{9,10,11,12},{13,14,15,16})) == int3x3(1,2,3,5,6,7,9,10,11));
@@ -83,6 +86,7 @@ TEST_CASE("vmath/mat") {
             STATIC_REQUIRE(int4x4(int4{2,3,4,5}) == int4x4(2,0,0,0,0,3,0,0,0,0,4,0,0,0,0,5));
             STATIC_REQUIRE(int4x4(1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16) == int4x4(1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16));
             STATIC_REQUIRE(int4x4({1,2,3,4},{5,6,7,8},{9,10,11,12},{13,14,15,16}) == int4x4(1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16));
+            STATIC_REQUIRE(int4x4(int3x3({1,2,3},{4,5,6},{7,8,9}),int3{10,11,12}) == int4x4(1,2,3,0,4,5,6,0,7,8,9,0,10,11,12,1));
             STATIC_REQUIRE(int4x4(int4x4({1,2,3,4},{5,6,7,8},{9,10,11,12},{13,14,15,16})) == int4x4(1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16));
             STATIC_REQUIRE(int4x4(int2x2({1,2},{3,4})) == int4x4(1,2,0,0,3,4,0,0,0,0,1,0,0,0,0,1));
             STATIC_REQUIRE(int4x4(int3x3({1,2,3},{4,5,6},{7,8,9})) == int4x4(1,2,3,0,4,5,6,0,7,8,9,0,0,0,0,1));