diff --git a/README.md b/README.md
index 0345e5c..ec96ec4 100644
--- a/README.md
+++ b/README.md
@@ -63,9 +63,7 @@ Run them by running `python setup.py test` (or `pytest`).
 ## Co-ordinate spaces
 
 sb-vision describes the locations of identified markers in either Cartesian or
-spherical co-ordinate spaces. A "legacy polar" co-ordinate space exists for
-backwards compatibility but is deprecated, undocumented and will be removed in
-May 2018.
+spherical co-ordinate spaces.
 
 ### Cartesian co-ordinates
 
diff --git a/sb_vision/__init__.py b/sb_vision/__init__.py
index 21b3492..692dba4 100644
--- a/sb_vision/__init__.py
+++ b/sb_vision/__init__.py
@@ -7,7 +7,7 @@
 """
 
 from .camera import Camera, FileCamera
-from .coordinates import Cartesian, LegacyPolar, Spherical, cartesian_to_spherical
+from .coordinates import Cartesian, Spherical, cartesian_to_spherical
 from .tokens import Token
 from .vision import Vision
 
@@ -17,7 +17,6 @@
     'FileCamera',
     'Token',
     'Cartesian',
-    'LegacyPolar',
     'Spherical',
     'cartesian_to_spherical',
 ]
diff --git a/sb_vision/coordinates.py b/sb_vision/coordinates.py
index 01b9154..17ef755 100644
--- a/sb_vision/coordinates.py
+++ b/sb_vision/coordinates.py
@@ -2,7 +2,6 @@
 
 from typing import NamedTuple, Union
 
-import numpy as np
 from numpy import arctan2, float64, linalg
 
 AnyFloat = Union[float, float64]
@@ -30,13 +29,6 @@ def tolist(self):
     ('dist', AnyFloat),
 ))
 
-LegacyPolar = NamedTuple('LegacyPolar', (
-    ('polar_x', AnyFloat),
-    ('polar_y', AnyFloat),
-    ('dist', AnyFloat),
-))
-
-
 PixelCoordinate = NamedTuple('PixelCoordinate', [('x', AnyFloat), ('y', AnyFloat)])
 
 
@@ -48,16 +40,3 @@ def cartesian_to_spherical(cartesian: Cartesian) -> Spherical:
         rot_y=arctan2(x, z),
         dist=linalg.norm(cartesian),
     )
-
-
-def cartesian_to_legacy_polar(cartesian: Cartesian) -> LegacyPolar:
-    """
-    Convert cartesian co-ordinate space to the legacy "polar" space.
-
-    This is kept for compatibility only.
-    """
-    cart_x, cart_y, cart_z = tuple(cartesian)
-    polar_dist = np.linalg.norm(cartesian)
-    polar_x = np.arctan2(cart_z, cart_x)
-    polar_y = np.arctan2(cart_z, cart_y)
-    return LegacyPolar(polar_x, polar_y, polar_dist)
diff --git a/sb_vision/tokens.py b/sb_vision/tokens.py
index f8b003c..b569013 100644
--- a/sb_vision/tokens.py
+++ b/sb_vision/tokens.py
@@ -4,11 +4,7 @@
 
 import numpy as np
 
-from .coordinates import (
-    Cartesian,
-    cartesian_to_legacy_polar,
-    cartesian_to_spherical,
-)
+from .coordinates import Cartesian, cartesian_to_spherical
 from .find_3D_coords import (
     PixelCoordinate,
     calculate_transforms,
@@ -110,9 +106,6 @@ def update_3D_transforms(
         self.cartesian = translation
 
         # Polar co-ordinates in the 3D world, relative to the camera
-        self.polar = cartesian_to_legacy_polar(self.cartesian)
-        self.legacy_polar = cartesian_to_legacy_polar(self.cartesian)
-
         self.spherical = cartesian_to_spherical(self.cartesian)
 
     def __repr__(self) -> str:
diff --git a/tests/test_coordinates_from_file.py b/tests/test_coordinates_from_file.py
index b5d7a37..a08d9e2 100644
--- a/tests/test_coordinates_from_file.py
+++ b/tests/test_coordinates_from_file.py
@@ -6,7 +6,7 @@
 import pytest
 from pytest import approx
 
-from sb_vision import Cartesian, FileCamera, LegacyPolar, Spherical, Vision
+from sb_vision import Cartesian, FileCamera, Spherical, Vision
 
 # Ensure all distance values are within this tolerance
 # (as a percentage of the total distance)
@@ -20,11 +20,6 @@
     (
         '1.0z-0.1x.jpg',
         Cartesian(x=-0.1, y=0, z=1),
-        LegacyPolar(
-            polar_x=1.6704649792860642,
-            polar_y=1.5707963267948966,
-            dist=1.004987562112089,
-        ),
         Spherical(
             rot_x=0,
             rot_y=math.atan(-0.1),  # or -5.710593137499643 degrees
@@ -34,11 +29,6 @@
     (
         '3.0z1.0x.jpg',
         Cartesian(x=1, y=0, z=3),
-        LegacyPolar(
-            polar_x=1.1922,
-            polar_y=1.6032,
-            dist=(1 + 9)**0.5,  # or 3.1622776601683795
-        ),
         Spherical(
             rot_x=0,
             rot_y=math.atan(1 / 3),  # or 18.43494882296774 degrees
@@ -49,10 +39,10 @@
 
 
 @pytest.mark.parametrize(
-    "photo, expected_cartesian, expected_polar, expected_spherical",
+    "photo, expected_cartesian, expected_spherical",
     TEST_IMAGES,
 )
-def test_image_coordinates(photo, expected_cartesian, expected_polar, expected_spherical):
+def test_image_coordinates(photo, expected_cartesian, expected_spherical):
     """Make sure that this particular file gives these particular tokens."""
     camera = FileCamera(CALIBRATIONS / photo, camera_model='C016')
     vision = Vision(camera)
@@ -70,12 +60,6 @@ def approx_ang(expected):
     assert y == approx_dist(expected_cartesian.y), "Wrong y-coordinate"
     assert z == approx_dist(expected_cartesian.z), "Wrong z-coordinate"
 
-    polar_x, polar_y, polar_dist = token.legacy_polar
-
-    assert polar_x == approx_ang(expected_polar.polar_x), "Wrong polar_x coordinate"
-    assert polar_y == approx_ang(expected_polar.polar_y), "Wrong polar_y coordinate"
-    assert polar_dist == approx_dist(expected_polar.dist), "Wrong polar_dist coordinate"
-
     rot_x, rot_y, dist = token.spherical
 
     assert rot_x == approx_ang(expected_spherical.rot_x), "Wrong x-coordinate"