diff --git a/src/sm_bluesky/beamlines/i05/configuration/__init__.py b/src/sm_bluesky/beamlines/i05/configuration/__init__.py
new file mode 100644
index 00000000..e69de29b
diff --git a/src/sm_bluesky/beamlines/i05/configuration/constants.py b/src/sm_bluesky/beamlines/i05/configuration/constants.py
new file mode 100644
index 00000000..ab212133
--- /dev/null
+++ b/src/sm_bluesky/beamlines/i05/configuration/constants.py
@@ -0,0 +1,13 @@
+import numpy as np
+
+M3MJ6_X_POLY_1600 = np.array([6.2625, -0.010313, 0.0], dtype=np.float64)
+M3MJ6_X_POLY_800 = np.array([6.2017, -0.010049, 0.0], dtype=np.float64)
+
+M3MJ6_PITCH_POLY_1600 = np.array(
+    [4528.4, 0.63741, -1.9103e-4, 5.7109e-8],
+    dtype=np.float64,
+)
+M3MJ6_PITCH_POLY_800 = np.array(
+    [4460.8, 0.66544, -0.00017244, 4.4545e-8],
+    dtype=np.float64,
+)
diff --git a/src/sm_bluesky/beamlines/i05/plans/__init__.py b/src/sm_bluesky/beamlines/i05/plans/__init__.py
new file mode 100644
index 00000000..e69de29b
diff --git a/src/sm_bluesky/beamlines/i05/plans/m1m3_alignment.py b/src/sm_bluesky/beamlines/i05/plans/m1m3_alignment.py
new file mode 100644
index 00000000..824ed8ff
--- /dev/null
+++ b/src/sm_bluesky/beamlines/i05/plans/m1m3_alignment.py
@@ -0,0 +1,147 @@
+from bluesky.plans import grid_scan
+from bluesky.utils import MsgGenerator, plan
+from dodal.beamlines.i05 import devices as i05_devices
+from dodal.common import inject
+from dodal.device_manager import DeviceManager
+from dodal.devices.beamlines.i05_shared import Grating, PolynomCompoundMotors
+from dodal.devices.common_mirror import XYZPiezoSwitchingMirror
+from dodal.devices.motors import XYZPitchYawRollStage
+from dodal.devices.pgm import PlaneGratingMonochromator
+from ophyd_async.core import StandardReadable, StrictEnum
+
+from sm_bluesky.beamlines.i05.configuration.constants import (
+    M3MJ6_PITCH_POLY_800,
+    M3MJ6_PITCH_POLY_1600,
+    M3MJ6_X_POLY_800,
+    M3MJ6_X_POLY_1600,
+)
+
+# At this point in the alignment, we already have nice parameters for the dependence of
+# m3mj6_x, but we want to establish the dependence of m3mj6_pitch vs m1es_pitch.
+# The GDA scan command would be something like:
+# scan m1es_pitch -200 1600 75 m3mj6_pitch 4750 5350 8 waittime 0.1 dj7current_new
+# We then need to fit the peak at each value of m1es_pitch, and from the peak positions
+# we fit a third order polynomial. With m1es_pitch then well established, we
+# subsequently do the focusing scan using the gas cell.
+#
+# This scan actually takes over an hour, because the step motion of the hexapod
+# (m3mj6_pitch) is slow. In principle we could try to do it in a "fly" mode
+# with bluesky, which could be a significant speed up.
+
+# Define alignment devices and factory functions to create them.
+alignment_devices = DeviceManager()
+
+
+# This is a temp polynomial compound motor that maps the m1es_pitch to the already
+# defined m3mj6_x for finding m3 pitch dependence on m1es_pitch. Once we have the
+# m3mj6_pitch dependence on m1es_pitch, we can then define the real polynomial
+# compound motor for m3mj6_pitch and forget this temp one
+@alignment_devices.factory()
+def m1_m3_x_800(
+    m1_collimating_mirror: XYZPitchYawRollStage,
+    m3mj6_switching_mirror: XYZPiezoSwitchingMirror,
+) -> PolynomCompoundMotors:
+    return PolynomCompoundMotors(
+        m1_collimating_mirror.pitch,
+        {
+            m3mj6_switching_mirror.x: M3MJ6_X_POLY_800,
+        },
+    )
+
+
+# This is a temp polynomial compound motor that maps the m1es_pitch to the already
+# defined m3mj6_x for finding m3 pitch dependence on m1es_pitch. Once we have the
+# m3mj6_pitch dependence on m1es_pitch, we can then define the real polynomial
+# compound motor for m3mj6_pitch and forget this temp one
+@alignment_devices.factory()
+def m1_m3_x_1600(
+    m1_collimating_mirror: XYZPitchYawRollStage,
+    m3mj6_switching_mirror: XYZPiezoSwitchingMirror,
+) -> PolynomCompoundMotors:
+    return PolynomCompoundMotors(
+        m1_collimating_mirror.pitch,
+        {
+            m3mj6_switching_mirror.x: M3MJ6_X_POLY_1600,
+        },
+    )
+
+
+# This is a final polynomial compound motor that maps the m1es_pitch to the
+# m3mj6_x for and m3 pitch.
+@alignment_devices.factory()
+def m1_m3_x_pitch_800(
+    m1_collimating_mirror: XYZPitchYawRollStage,
+    m3mj6_switching_mirror: XYZPiezoSwitchingMirror,
+) -> PolynomCompoundMotors:
+    return PolynomCompoundMotors(
+        m1_collimating_mirror.pitch,
+        {
+            m3mj6_switching_mirror.x: M3MJ6_X_POLY_800,
+            m3mj6_switching_mirror.pitch: M3MJ6_PITCH_POLY_800,
+        },
+    )
+
+
+# This is a final polynomial compound motor that maps the m1es_pitch to the
+# m3mj6_x for and m3 pitch.
+@alignment_devices.factory()
+def m1_m3_x_pitch_1600(
+    m1_collimating_mirror: XYZPitchYawRollStage,
+    m3mj6_switching_mirror: XYZPiezoSwitchingMirror,
+) -> PolynomCompoundMotors:
+    return PolynomCompoundMotors(
+        m1_collimating_mirror.pitch,
+        {
+            m3mj6_switching_mirror.x: M3MJ6_X_POLY_1600,
+            m3mj6_switching_mirror.pitch: M3MJ6_PITCH_POLY_1600,
+        },
+    )
+
+
+i05_devices.include(alignment_devices)
+
+
+# This will produce 2D map of m1es_pitch vs m3mj6_pitch, with the intensity of
+# dj7current_new as the value. We then fit the peak at each value of m1es_pitch,
+# and from the peak positions we fit a third order polynomial to find the dependence
+# of m3mj6_pitch on m1es_pitch. This will amend M3MJ6_PITCH_POLY_800/1600.
+# With m1es_pitch then well established,
+# we subsequently do the focusing scan using the gas cell.
+@plan
+def map_m1_m3_mirrors(
+    m1_start: float,
+    m1_end: float,
+    m1_num: int,
+    m3_start: float,
+    m3_end: float,
+    m3_num: int,
+    det: StandardReadable = inject("dj7current_new"),
+    m3: XYZPiezoSwitchingMirror = inject("m3mj6_switching_mirror"),
+) -> MsgGenerator:
+    """
+    Plan to find optimal alignment of the M1.pitch and M3MJ6.pitch mirrors
+    """
+    if get_pgm_grating() == Grating.PT_800:
+        m1_pitch = inject("m1_m3_x_800")
+    elif get_pgm_grating() == Grating.C_1600:
+        m1_pitch = inject("m1_m3_x_1600")
+    else:
+        raise ValueError("Unsupported grating for M1-M3 alignment.")
+    yield from grid_scan(
+        [det],
+        m1_pitch,
+        m1_start,
+        m1_end,
+        m1_num,
+        m3.pitch,
+        m3_start,
+        m3_end,
+        m3_num,
+    )
+
+
+async def get_pgm_grating(
+    pgm: PlaneGratingMonochromator = inject("pgm"),
+) -> StrictEnum:
+    reading = await pgm.grating.get_value()
+    return reading