diff --git a/src/approx.rs b/src/approx.rs
index 72deb3a..13cc2dc 100644
--- a/src/approx.rs
+++ b/src/approx.rs
@@ -49,7 +49,7 @@ macro_rules! assert_approx_eq_eps(
         let eps = &($eps);
         let (given_val, expected_val) = (&($given), &($expected));
         if !given_val.approx_eq_eps(expected_val, eps) {
-            fail!("assertion failed: `left ≈ right` (left: `{}`, right: `{}`, tolerance: `{}`)",
+            panic!("assertion failed: `left ≈ right` (left: `{}`, right: `{}`, tolerance: `{}`)",
                 *given_val, *expected_val, *eps
             )
         }
@@ -61,7 +61,7 @@ macro_rules! assert_approx_eq(
     ($given: expr, $expected: expr) => ({
         let (given_val, expected_val) = (&($given), &($expected));
         if !given_val.approx_eq(expected_val) {
-            fail!("assertion failed: `left ≈ right` (left: `{}`, right: `{}`, tolerance: `{}`)",
+            panic!("assertion failed: `left ≈ right` (left: `{}`, right: `{}`, tolerance: `{}`)",
                 *given_val, *expected_val,
                 ApproxEq::approx_epsilon(Some(*given_val))
             )
diff --git a/src/matrix.rs b/src/matrix.rs
index 4054388..4f5df4f 100644
--- a/src/matrix.rs
+++ b/src/matrix.rs
@@ -422,7 +422,7 @@ impl<S> FixedArray<[[S, ..2], ..2]> for Matrix2<S> {
         //         y: FixedArray::from_fixed(y),
         //     },
         // }
-        fail!("Unimplemented, pending a fix for rust-lang/rust#16418")
+        panic!("Unimplemented, pending a fix for rust-lang/rust#16418")
     }
 
     #[inline]
@@ -502,7 +502,7 @@ impl<S> FixedArray<[[S, ..3], ..3]> for Matrix3<S> {
         //         z: FixedArray::from_fixed(z),
         //     },
         // }
-        fail!("Unimplemented, pending a fix for rust-lang/rust#16418")
+        panic!("Unimplemented, pending a fix for rust-lang/rust#16418")
     }
 
     #[inline]
@@ -587,7 +587,7 @@ impl<S> FixedArray<[[S, ..4], ..4]> for Matrix4<S> {
         //         w: FixedArray::from_fixed(w),
         //     },
         // }
-        fail!("Unimplemented, pending a fix for rust-lang/rust#16418")
+        panic!("Unimplemented, pending a fix for rust-lang/rust#16418")
     }
 
     #[inline]
@@ -1095,7 +1095,7 @@ impl<S: BaseFloat + 'static> Matrix<S, Vector4<S>> for Matrix4<S> {
                     3 => Matrix3::from_cols(t.x.truncate_n(j),
                                             t.y.truncate_n(j),
                                             t.z.truncate_n(j)),
-                    _ => fail!("out of range")
+                    _ => panic!("out of range")
                 };
                 let sign = if (i+j) & 1 == 1 {-one} else {one};
                 mat.determinant() * sign * inv_det
diff --git a/src/plane.rs b/src/plane.rs
index 191f0a1..1de0153 100644
--- a/src/plane.rs
+++ b/src/plane.rs
@@ -111,13 +111,13 @@ impl<S: BaseFloat> Intersect<Option<Point3<S>>> for (Plane<S>, Ray3<S>) {
 
 impl<S: BaseFloat> Intersect<Option<Ray3<S>>> for (Plane<S>, Plane<S>) {
     fn intersection(&self) -> Option<Ray3<S>> {
-        fail!("Not yet implemented");
+        panic!("Not yet implemented");
     }
 }
 
 impl<S: BaseFloat> Intersect<Option<Point3<S>>> for (Plane<S>, Plane<S>, Plane<S>) {
     fn intersection(&self) -> Option<Point3<S>> {
-        fail!("Not yet implemented");
+        panic!("Not yet implemented");
     }
 }
 
diff --git a/src/point.rs b/src/point.rs
index 2f01e11..6667781 100644
--- a/src/point.rs
+++ b/src/point.rs
@@ -121,7 +121,7 @@ impl<S> FixedArray<[S, ..2]> for Point2<S> {
     #[inline]
     fn from_fixed(_v: [S, ..2]) -> Point2<S> {
         // match v { [x, y] => Point2 { x: x, y: y } }
-        fail!("Unimplemented, pending a fix for rust-lang/rust#16418")
+        panic!("Unimplemented, pending a fix for rust-lang/rust#16418")
     }
 
     #[inline]
@@ -275,7 +275,7 @@ impl<S> FixedArray<[S, ..3]> for Point3<S> {
     #[inline]
     fn from_fixed(_v: [S, ..3]) -> Point3<S> {
         // match v { [x, y, z] => Point3 { x: x, y: y, z: z } }
-        fail!("Unimplemented, pending a fix for rust-lang/rust#16418")
+        panic!("Unimplemented, pending a fix for rust-lang/rust#16418")
     }
 
     #[inline]
diff --git a/src/vector.rs b/src/vector.rs
index 9922860..27f71e0 100644
--- a/src/vector.rs
+++ b/src/vector.rs
@@ -231,7 +231,7 @@ macro_rules! vec(
             #[inline]
             fn from_fixed(_v: [$S, ..$n]) -> $Self<$S> {
                 // match v { [$($field),+] => $Self { $($field: $field),+ } }
-                fail!("Unimplemented, pending a fix for rust-lang/rust#16418")
+                panic!("Unimplemented, pending a fix for rust-lang/rust#16418")
             }
 
             #[inline]
@@ -438,7 +438,7 @@ impl<S: BaseNum> Vector4<S> {
             1 => Vector3::new(self.x, self.z, self.w),
             2 => Vector3::new(self.x, self.y, self.w),
             3 => Vector3::new(self.x, self.y, self.z),
-            _ => fail!("{} is out of range", n)
+            _ => panic!("{} is out of range", n)
         }
     }
 }
diff --git a/tests/quaternion.rs b/tests/quaternion.rs
index 3f64b68..781e6fe 100644
--- a/tests/quaternion.rs
+++ b/tests/quaternion.rs
@@ -43,7 +43,7 @@ fn to_and_from_quaternion()
         if !(ax.approx_eq_eps(&bx, &0.001) &&
              ay.approx_eq_eps(&by, &0.001) &&
              az.approx_eq_eps(&bz, &0.001)) {
-            fail!("{} != {}", a, b)
+            panic!("{} != {}", a, b)
         }
     }