diff --git a/pacman/model/graphs/abstract_multiple_partition.py b/pacman/model/graphs/abstract_multiple_partition.py
index 50ec48529..d3edad63a 100644
--- a/pacman/model/graphs/abstract_multiple_partition.py
+++ b/pacman/model/graphs/abstract_multiple_partition.py
@@ -13,8 +13,7 @@
 # You should have received a copy of the GNU General Public License
 # along with this program.  If not, see <http://www.gnu.org/licenses/>.
 
-from collections import OrderedDict
-from spinn_utilities.default_ordered_dict import DefaultOrderedDict
+from collections import defaultdict
 from spinn_utilities.ordered_set import OrderedSet
 from spinn_utilities.overrides import overrides
 from pacman.exceptions import PacmanConfigurationException
@@ -38,8 +37,8 @@ def __init__(
             identifier=identifier,
             allowed_edge_types=allowed_edge_types, constraints=constraints,
             label=label, traffic_weight=traffic_weight, class_name=class_name)
-        self._pre_vertices = OrderedDict()
-        self._destinations = DefaultOrderedDict(OrderedSet)
+        self._pre_vertices = dict()
+        self._destinations = defaultdict(OrderedSet)
 
         # hard code dict of lists so that only these are acceptable.
         for pre_vertex in pre_vertices:
diff --git a/pacman/model/graphs/application/application_graph.py b/pacman/model/graphs/application/application_graph.py
index 3747fd41e..7d1647c7a 100644
--- a/pacman/model/graphs/application/application_graph.py
+++ b/pacman/model/graphs/application/application_graph.py
@@ -13,10 +13,10 @@
 # You should have received a copy of the GNU General Public License
 # along with this program.  If not, see <http://www.gnu.org/licenses/>.
 
+from collections import defaultdict
 from .application_edge import ApplicationEdge
 from .application_vertex import ApplicationVertex
 from .application_edge_partition import ApplicationEdgePartition
-from spinn_utilities.default_ordered_dict import DefaultOrderedDict
 from spinn_utilities.ordered_set import OrderedSet
 from spinn_utilities.overrides import overrides
 from pacman.exceptions import (
@@ -40,7 +40,7 @@ def __init__(self, label):
         """
         super().__init__(ApplicationVertex, ApplicationEdge, label)
         self._outgoing_edge_partitions_by_pre_vertex = \
-            DefaultOrderedDict(OrderedSet)
+            defaultdict(OrderedSet)
 
     def forget_machine_graph(self):
         """ Forget the whole mapping from this graph to an application graph.
diff --git a/pacman/model/graphs/graph.py b/pacman/model/graphs/graph.py
index 95338ff3a..19d1e88cb 100644
--- a/pacman/model/graphs/graph.py
+++ b/pacman/model/graphs/graph.py
@@ -13,10 +13,9 @@
 # You should have received a copy of the GNU General Public License
 # along with this program.  If not, see <http://www.gnu.org/licenses/>.
 
-from collections import OrderedDict
+from collections import defaultdict
 from spinn_utilities.abstract_base import (
     AbstractBase, abstractmethod, abstractproperty)
-from spinn_utilities.default_ordered_dict import DefaultOrderedDict
 from spinn_utilities.ordered_set import OrderedSet
 from pacman.exceptions import (
     PacmanAlreadyExistsException, PacmanInvalidParameterException)
@@ -72,11 +71,11 @@ def __init__(self, allowed_vertex_types, allowed_edge_types, label):
         self._vertices = []
         self._vertex_by_label = dict()
         self._unlabelled_vertex_count = 0
-        self._outgoing_edge_partitions_by_name = OrderedDict()
-        self._outgoing_edges = DefaultOrderedDict(OrderedSet)
-        self._incoming_edges = DefaultOrderedDict(OrderedSet)
-        self._incoming_edges_by_partition_name = DefaultOrderedDict(list)
-        self._outgoing_edge_partition_by_edge = OrderedDict()
+        self._outgoing_edge_partitions_by_name = dict()
+        self._outgoing_edges = defaultdict(OrderedSet)
+        self._incoming_edges = defaultdict(OrderedSet)
+        self._incoming_edges_by_partition_name = defaultdict(list)
+        self._outgoing_edge_partition_by_edge = dict()
         self._label = label
 
     @property
diff --git a/pacman/model/graphs/machine/machine_graph.py b/pacman/model/graphs/machine/machine_graph.py
index 16d85de5b..05be4e2d8 100644
--- a/pacman/model/graphs/machine/machine_graph.py
+++ b/pacman/model/graphs/machine/machine_graph.py
@@ -13,11 +13,11 @@
 # You should have received a copy of the GNU General Public License
 # along with this program.  If not, see <http://www.gnu.org/licenses/>.
 
+from collections import defaultdict
 from .machine_vertex import MachineVertex
 from .machine_edge import MachineEdge
 from spinn_utilities.ordered_set import OrderedSet
 from spinn_utilities.overrides import overrides
-from spinn_utilities.default_ordered_dict import DefaultOrderedDict
 from pacman.exceptions import (
     PacmanAlreadyExistsException, PacmanInvalidParameterException)
 from pacman.model.graphs import Graph
@@ -79,21 +79,21 @@ def __init__(self, label, application_graph=None):
         else:
             # Must be false as there is no App_graph
             self._application_level_used = False
-        self._multicast_partitions = DefaultOrderedDict(
-            lambda: DefaultOrderedDict(set))
+        self._multicast_partitions = defaultdict(
+            lambda: defaultdict(set))
         self._edge_partitions = OrderedSet()
         self._fixed_route_edge_partitions_by_pre_vertex = (
-            DefaultOrderedDict(OrderedSet))
+            defaultdict(OrderedSet))
         self._multicast_edge_partitions_by_pre_vertex = (
-            DefaultOrderedDict(OrderedSet))
+            defaultdict(OrderedSet))
         self._sdram_edge_partitions_by_pre_vertex = (
-            DefaultOrderedDict(OrderedSet))
+            defaultdict(OrderedSet))
         self._fixed_route_edge_partitions_by_post_vertex = (
-            DefaultOrderedDict(OrderedSet))
+            defaultdict(OrderedSet))
         self._multicast_edge_partitions_by_post_vertex = (
-            DefaultOrderedDict(OrderedSet))
+            defaultdict(OrderedSet))
         self._sdram_edge_partitions_by_post_vertex = (
-            DefaultOrderedDict(OrderedSet))
+            defaultdict(OrderedSet))
 
     @overrides(Graph.add_edge)
     def add_edge(self, edge, outgoing_edge_partition_name):
diff --git a/pacman/model/partitioner_splitters/abstract_splitters/abstract_splitter_common.py b/pacman/model/partitioner_splitters/abstract_splitters/abstract_splitter_common.py
index 576046bd8..655745a52 100644
--- a/pacman/model/partitioner_splitters/abstract_splitters/abstract_splitter_common.py
+++ b/pacman/model/partitioner_splitters/abstract_splitters/abstract_splitter_common.py
@@ -13,7 +13,6 @@
 # You should have received a copy of the GNU General Public License
 # along with this program.  If not, see <http://www.gnu.org/licenses/>.
 import sys
-from collections import OrderedDict
 from spinn_utilities.abstract_base import AbstractBase, abstractmethod
 from pacman.exceptions import PacmanConfigurationException
 from pacman.model.constraints.partitioner_constraints import (
@@ -85,7 +84,7 @@ def _get_map(self, edge_types):
         :return: dict of vertex as key, edge types as list in value
         :rtype: dict(MachineVertex, EdgeType)
         """
-        result = OrderedDict()
+        result = dict()
         for vertex in self._governed_app_vertex.machine_vertices:
             result[vertex] = edge_types
         return result
diff --git a/pacman/model/placements/placements.py b/pacman/model/placements/placements.py
index 855daeba2..ce303e1d2 100644
--- a/pacman/model/placements/placements.py
+++ b/pacman/model/placements/placements.py
@@ -13,7 +13,6 @@
 # You should have received a copy of the GNU General Public License
 # along with this program.  If not, see <http://www.gnu.org/licenses/>.
 
-from collections import OrderedDict
 from pacman.exceptions import (
     PacmanAlreadyPlacedError, PacmanNotPlacedError,
     PacmanProcessorAlreadyOccupiedError, PacmanProcessorNotOccupiedError)
@@ -41,8 +40,8 @@ def __init__(self, placements=None):
         :raise PacmanProcessorAlreadyOccupiedError:
             If two placements are made to the same processor.
         """
-        self._placements = OrderedDict()
-        self._machine_vertices = OrderedDict()
+        self._placements = dict()
+        self._machine_vertices = dict()
         if placements is not None:
             self.add_placements(placements)
 
diff --git a/pacman/model/routing_table_by_partition/multicast_routing_table_by_partition.py b/pacman/model/routing_table_by_partition/multicast_routing_table_by_partition.py
index baf48b224..f49755ca0 100644
--- a/pacman/model/routing_table_by_partition/multicast_routing_table_by_partition.py
+++ b/pacman/model/routing_table_by_partition/multicast_routing_table_by_partition.py
@@ -13,8 +13,6 @@
 # You should have received a copy of the GNU General Public License
 # along with this program.  If not, see <http://www.gnu.org/licenses/>.
 
-from collections import OrderedDict
-
 
 class MulticastRoutingTableByPartition(object):
     """ A set of multicast routing path objects
@@ -26,7 +24,7 @@ class MulticastRoutingTableByPartition(object):
     ]
 
     def __init__(self):
-        self._router_to_entries_map = OrderedDict()
+        self._router_to_entries_map = dict()
 
     def add_path_entry(self, entry, router_x, router_y, partition):
         """ Adds a multicast routing path entry
@@ -41,7 +39,7 @@ def add_path_entry(self, entry, router_x, router_y, partition):
         # update router_to_entries_map
         key = (router_x, router_y)
         if key not in self._router_to_entries_map:
-            self._router_to_entries_map[key] = OrderedDict()
+            self._router_to_entries_map[key] = dict()
 
         if partition not in self._router_to_entries_map[key]:
             self._router_to_entries_map[key][partition] = entry
diff --git a/pacman/model/routing_tables/multicast_routing_tables.py b/pacman/model/routing_tables/multicast_routing_tables.py
index b00ab9c3f..1d6eaf98a 100644
--- a/pacman/model/routing_tables/multicast_routing_tables.py
+++ b/pacman/model/routing_tables/multicast_routing_tables.py
@@ -15,7 +15,6 @@
 
 import json
 import gzip
-from collections import OrderedDict
 from pacman.exceptions import PacmanAlreadyExistsException
 from .uncompressed_multicast_routing_table import \
     UnCompressedMulticastRoutingTable
@@ -119,12 +118,12 @@ def __iter__(self):
 def to_json(router_table):
     json_list = []
     for routing_table in router_table:
-        json_routing_table = OrderedDict()
+        json_routing_table = dict()
         json_routing_table["x"] = routing_table.x
         json_routing_table["y"] = routing_table.y
         entries = []
         for entry in routing_table.multicast_routing_entries:
-            json_entry = OrderedDict()
+            json_entry = dict()
             json_entry["key"] = entry.routing_entry_key
             json_entry["mask"] = entry.mask
             json_entry["defaultable"] = entry.defaultable
diff --git a/pacman/model/routing_tables/uncompressed_multicast_routing_table.py b/pacman/model/routing_tables/uncompressed_multicast_routing_table.py
index fc98ae156..3d53345af 100644
--- a/pacman/model/routing_tables/uncompressed_multicast_routing_table.py
+++ b/pacman/model/routing_tables/uncompressed_multicast_routing_table.py
@@ -13,7 +13,6 @@
 # You should have received a copy of the GNU General Public License
 # along with this program.  If not, see <http://www.gnu.org/licenses/>.
 
-from collections import OrderedDict
 import csv
 import gzip
 import logging
@@ -70,7 +69,7 @@ def __init__(self, x, y, multicast_routing_entries=None):
         self._y = y
         self._number_of_defaulted_routing_entries = 0
         self._multicast_routing_entries = list()
-        self._entries_by_key_mask = OrderedDict()
+        self._entries_by_key_mask = dict()
         self._entries_by_key = dict()
 
         if multicast_routing_entries is not None:
diff --git a/pacman/operations/partition_algorithms/splitter_partitioner.py b/pacman/operations/partition_algorithms/splitter_partitioner.py
index be7db2e54..34ef24a7a 100644
--- a/pacman/operations/partition_algorithms/splitter_partitioner.py
+++ b/pacman/operations/partition_algorithms/splitter_partitioner.py
@@ -13,7 +13,6 @@
 # You should have received a copy of the GNU General Public License
 # along with this program.  If not, see <http://www.gnu.org/licenses/>.
 
-from collections import OrderedDict
 from pacman.exceptions import (PacmanConfigurationException)
 from pacman.model.constraints.partitioner_constraints import (
     MaxVertexAtomsConstraint, FixedVertexAtomsConstraint)
@@ -157,7 +156,7 @@ def order_vertices_for_dependent_splitters(self, vertices):
         :return: vertices in list with new ordering
         :rtype: iterable(ApplicationVertex)
         """
-        dependent_vertices = OrderedDict()
+        dependent_vertices = dict()
         other_vertices = set()
         for vertex in vertices:
             if isinstance(vertex.splitter, AbstractDependentSplitter):
diff --git a/pacman/operations/router_compressors/routing_compression_checker.py b/pacman/operations/router_compressors/routing_compression_checker.py
index 4beafe85e..eacc19870 100644
--- a/pacman/operations/router_compressors/routing_compression_checker.py
+++ b/pacman/operations/router_compressors/routing_compression_checker.py
@@ -13,7 +13,6 @@
 # You should have received a copy of the GNU General Public License
 # along with this program.  If not, see <http://www.gnu.org/licenses/>.
 
-from collections import OrderedDict
 import logging
 from spinn_utilities.log import FormatAdapter
 from pacman.exceptions import PacmanRoutingException
@@ -62,7 +61,7 @@ def codify_table(table, length=32):
     :param int length:
     :rtype: dict(str, ~spinn_machine.MulticastRoutingEntry)
     """
-    code_dict = OrderedDict()
+    code_dict = dict()
     for route in table.multicast_routing_entries:
         code_dict[codify(route, length)] = route
     return code_dict
diff --git a/pacman/operations/routing_table_generators/zoned_routing_table_generator.py b/pacman/operations/routing_table_generators/zoned_routing_table_generator.py
index a36b6158a..47a57fcb1 100644
--- a/pacman/operations/routing_table_generators/zoned_routing_table_generator.py
+++ b/pacman/operations/routing_table_generators/zoned_routing_table_generator.py
@@ -13,8 +13,8 @@
 # You should have received a copy of the GNU General Public License
 # along with this program.  If not, see <http://www.gnu.org/licenses/>.
 
+from collections import defaultdict
 from spinn_utilities.progress_bar import ProgressBar
-from spinn_utilities.default_ordered_dict import DefaultOrderedDict
 from spinn_machine import MulticastRoutingEntry
 from pacman.model.routing_tables import (
     UnCompressedMulticastRoutingTable, MulticastRoutingTables)
@@ -89,7 +89,7 @@ def _create_routing_table(self, chip, partitions_in_table, routing_infos,
         :rtype: MulticastRoutingTable
         """
         table = UnCompressedMulticastRoutingTable(chip.x, chip.y)
-        partitions_by_app_vertex = DefaultOrderedDict(set)
+        partitions_by_app_vertex = defaultdict(set)
         for partition in partitions_in_table:
             partitions_by_app_vertex[partition.pre_vertex.app_vertex].add(
                 partition)
diff --git a/pacman/utilities/algorithm_utilities/partition_algorithm_utilities.py b/pacman/utilities/algorithm_utilities/partition_algorithm_utilities.py
index 4ae33019a..882cabe5c 100644
--- a/pacman/utilities/algorithm_utilities/partition_algorithm_utilities.py
+++ b/pacman/utilities/algorithm_utilities/partition_algorithm_utilities.py
@@ -16,7 +16,6 @@
 """ A collection of methods which support partitioning algorithms.
 """
 
-from collections import OrderedDict
 from spinn_utilities.ordered_set import OrderedSet
 from pacman.utilities import utility_calls as utils
 from pacman.exceptions import PacmanPartitionException
@@ -82,7 +81,7 @@ def get_same_size_vertex_groups(vertices):
 
     # Dict of vertex to list of vertices with same size
     # (repeated lists expected)
-    same_size_vertices = OrderedDict()
+    same_size_vertices = dict()
 
     for vertex in vertices:
 
diff --git a/pacman/utilities/algorithm_utilities/placer_algorithm_utilities.py b/pacman/utilities/algorithm_utilities/placer_algorithm_utilities.py
index fbba11dfa..397db0d14 100644
--- a/pacman/utilities/algorithm_utilities/placer_algorithm_utilities.py
+++ b/pacman/utilities/algorithm_utilities/placer_algorithm_utilities.py
@@ -14,7 +14,6 @@
 # along with this program.  If not, see <http://www.gnu.org/licenses/>.
 
 import functools
-from collections import OrderedDict
 
 from pacman.model.resources import ResourceContainer, ConstantSDRAM
 from spinn_utilities.ordered_set import OrderedSet
@@ -75,7 +74,7 @@ def get_same_chip_vertex_groups(graph):
         get_vertices_on_same_chip, graph=graph))
     # Dict of vertex to set of vertices on same chip (repeated lists expected)
     # A empty set value indicates a set that is too big.
-    same_chip_vertices = OrderedDict()
+    same_chip_vertices = dict()
     for group in groups:
         for vertex in group:
             same_chip_vertices[vertex] = group
diff --git a/pacman/utilities/algorithm_utilities/routing_info_allocator_utilities.py b/pacman/utilities/algorithm_utilities/routing_info_allocator_utilities.py
index 4f3c02d54..70669a0df 100644
--- a/pacman/utilities/algorithm_utilities/routing_info_allocator_utilities.py
+++ b/pacman/utilities/algorithm_utilities/routing_info_allocator_utilities.py
@@ -13,7 +13,6 @@
 # You should have received a copy of the GNU General Public License
 # along with this program.  If not, see <http://www.gnu.org/licenses/>.
 
-from collections import OrderedDict
 import logging
 from spinn_utilities.log import FormatAdapter
 from spinn_utilities.ordered_set import OrderedSet
@@ -81,7 +80,7 @@ def get_mulitcast_edge_groups(machine_graph):
     """
 
     # mapping between partition and shared key group it is in
-    partition_groups = OrderedDict()
+    partition_groups = dict()
 
     # process each partition one by one in a bubble sort kinda way
     for vertex in machine_graph.vertices:
diff --git a/pacman/utilities/json_utils.py b/pacman/utilities/json_utils.py
index 201443685..454f6f677 100644
--- a/pacman/utilities/json_utils.py
+++ b/pacman/utilities/json_utils.py
@@ -16,7 +16,6 @@
 Miscellaneous minor functions for converting between JSON and Python objects.
 """
 
-from collections import OrderedDict
 import json
 import gzip
 from pacman.model.constraints.key_allocator_constraints import (
@@ -78,7 +77,7 @@ def constraint_to_json(constraint):
     :return: A dict describing the constraint
     :rtype: dict
     """
-    json_dict = OrderedDict()
+    json_dict = dict()
     try:
         json_dict["class"] = constraint.__class__.__name__
         if isinstance(constraint, BoardConstraint):
@@ -167,7 +166,7 @@ def constraints_from_json(json_list, graph):
 
 def key_mask_to_json(key_mask):
     try:
-        json_object = OrderedDict()
+        json_object = dict()
         json_object["key"] = key_mask.key
         json_object["mask"] = key_mask.mask
     except Exception as ex:  # pylint: disable=broad-except
@@ -194,7 +193,7 @@ def key_masks_from_json(json_list):
 
 
 def resource_container_to_json(container):
-    json_dict = OrderedDict()
+    json_dict = dict()
     try:
         json_dict["dtcm"] = container.dtcm.get_value()
         json_dict["cpu_cycles"] = container.cpu_cycles.get_value()
@@ -221,7 +220,7 @@ def resource_container_from_json(json_dict):
 
 
 def iptag_resource_to_json(iptag):
-    json_dict = OrderedDict()
+    json_dict = dict()
     try:
         json_dict["ip_address"] = iptag.ip_address
         if iptag.port is not None:
@@ -258,7 +257,7 @@ def iptag_resources_from_json(json_list):
 
 
 def vertex_to_json(vertex):
-    json_dict = OrderedDict()
+    json_dict = dict()
     try:
         json_dict["class"] = vertex.__class__.__name__
         json_dict["label"] = vertex.label
@@ -289,7 +288,7 @@ def vertex_add_contstraints_from_json(json_dict, graph):
 
 
 def edge_to_json(edge):
-    json_dict = OrderedDict()
+    json_dict = dict()
     try:
         json_dict["pre_vertex"] = edge.pre_vertex.label
         json_dict["post_vertex"] = edge.post_vertex.label
@@ -312,7 +311,7 @@ def edge_from_json(json_dict, graph=None):
 
 def graph_to_json(graph):
     #  TODO Appplication vertex info needed for ZonedRoutingInfoAllocator
-    json_dict = OrderedDict()
+    json_dict = dict()
     try:
         if graph.label is not None:
             json_dict["label"] = graph.label
@@ -350,7 +349,7 @@ def vertex_lookup(label, graph=None):
 
 
 def placement_to_json(placement):
-    json_dict = OrderedDict()
+    json_dict = dict()
     try:
         json_dict["vertex_label"] = placement.vertex.label
         json_dict["x"] = placement.x
@@ -377,7 +376,7 @@ def placement_from_json(json_dict, graph=None):
 def partition_to_n_keys_map_to_json(partition_to_n_keys_map):
     json_list = []
     for partition in partition_to_n_keys_map:
-        json_dict = OrderedDict()
+        json_dict = dict()
         try:
             json_dict["pre_vertex_label"] = partition.pre_vertex.label
             json_dict["identifier"] = partition.identifier
diff --git a/pacman/utilities/vertex_sorter.py b/pacman/utilities/vertex_sorter.py
index 58a955fe5..8da0ceaf3 100644
--- a/pacman/utilities/vertex_sorter.py
+++ b/pacman/utilities/vertex_sorter.py
@@ -13,8 +13,8 @@
 # You should have received a copy of the GNU General Public License
 # along with this program.  If not, see <http://www.gnu.org/licenses/>.
 
+from collections import defaultdict
 import sys
-from spinn_utilities.default_ordered_dict import DefaultOrderedDict
 
 
 class ConstraintOrder(object):
@@ -91,7 +91,7 @@ def __init__(self, constraint_order):
             The order in which the constraints are to be sorted
         """
         # Group constraints based on the class
-        self._constraints = DefaultOrderedDict(list)
+        self._constraints = defaultdict(list)
         for c in constraint_order:
             self._constraints[c.constraint_class].append(
                 (c.relative_order, c.required_optional_properties))