diff --git a/usb_protocol/emitters/descriptors/cdc.py b/usb_protocol/emitters/descriptors/cdc.py
new file mode 100644
index 0000000..14f294a
--- /dev/null
+++ b/usb_protocol/emitters/descriptors/cdc.py
@@ -0,0 +1,15 @@
+#
+# This file is part of usb_protocol.
+#
+""" Convenience emitters for CDC descriptors. """
+
+from .. import emitter_for_format
+from ...types.descriptors.cdc import \
+    HeaderDescriptor, UnionFunctionalDescriptor, ACMFunctionalDescriptor, \
+    CallManagementFunctionalDescriptor
+
+# Create our emitters.
+HeaderDescriptorEmitter                   = emitter_for_format(HeaderDescriptor)
+UnionFunctionalDescriptorEmitter          = emitter_for_format(UnionFunctionalDescriptor)
+ACMFunctionalDescriptorEmitter            = emitter_for_format(ACMFunctionalDescriptor)
+CallManagementFunctionalDescriptorEmitter = emitter_for_format(CallManagementFunctionalDescriptor)
diff --git a/usb_protocol/types/descriptors/cdc.py b/usb_protocol/types/descriptors/cdc.py
new file mode 100644
index 0000000..103938d
--- /dev/null
+++ b/usb_protocol/types/descriptors/cdc.py
@@ -0,0 +1,83 @@
+#
+# This file is part of usb-protocol.
+#
+""" Structures describing Communications Device Class descriptors. """
+
+import unittest
+from enum import IntEnum
+
+import construct
+from   construct  import this, Default
+
+from .. import LanguageIDs
+from ..descriptor import \
+    DescriptorField, DescriptorNumber, DescriptorFormat, \
+    BCDFieldAdapter, DescriptorLength
+
+
+class CDCDescriptorNumbers(IntEnum):
+    CS_INTERFACE  = 0x24
+    CS_ENDPOINT   = 0x25
+
+
+class CDCDescriptorSubtypes(IntEnum):
+    """ Numbers of the Communications Class descriptor subtypes. """
+
+    HEADER                                    = 0x00
+    CALL_MANAGEMENT_FUNCTIONAL                = 0x01
+    ABSTRACT_CONTROL_MANAGEMENT_FUNCTIONAL    = 0x02
+    DIRECT_LINE_MANAGEMENT_FUNCTIONAL         = 0x03
+    TELEPHONE_RINGER_FUNCTIONAL               = 0x04
+    TELEPHONE_CALL_AND_LINE_STATE_FUNCTIONAL  = 0x05
+    UNION_FUNCTIONAL_DESCRIPTOR               = 0x06
+    COUNTRY_SELECTION_FUNCTIONAL              = 0x07
+    TELEPHONE_OPERATIONAL_MODES_FUNCTIONAL    = 0x08
+    USB_TERMINAL_FUNCTIONAL                   = 0x09
+    NETWORK_CHANNEL_TERMINAL                  = 0x0a
+    PROTOCOL_UNIT_FUNCTIONAL                  = 0x0b
+    EXTENSION_UNIT_FUNCTIONAL                 = 0x0c
+    MULTI_CHANNEL_MANAGEMENT_FUNCTIONAL       = 0x0d
+    CAPI_CONTROL_MANAGEMENT_FUNCTIONAL        = 0x0e
+    ETHERNET_NETWORKING_FUNCTIONAL            = 0x0f
+    ATM_NETWORKING_FUNCTIONAL                 = 0x10
+    WIRELESS_HANDSET_CONTROL_MODEL_FUNCTIONAL = 0x11
+    MOBILE_DIRECT_LINE_MODEL_FUNCTIONAL       = 0x12
+    MDLM_DETAIL_FUNCTIONAL                    = 0x13
+    DEVICE_MANAGEMENT_MODEL_FUNCTIONAL        = 0x14
+    OBEX_FUNCTIONAL                           = 0x15
+    COMMAND_SET_FUCNTIONAL                    = 0x16
+    COMMAND_SET_DETAIL_FUNCTIONAL             = 0x17
+    TELEPHONE_CONTROL_MODEL_FUNCTIONAL        = 0x18
+    OBEX_SERVICE_IDENTIFIER_FUNCTIONAL        = 0x19
+    NCM_FUNCTIONAL                            = 0x1A
+
+
+HeaderDescriptor = DescriptorFormat(
+    "bLength"             / construct.Const(5, construct.Int8ul),
+    "bDescriptorType"     / DescriptorNumber(CDCDescriptorNumbers.CS_INTERFACE),
+    "bDescriptorSubtype"  / DescriptorNumber(CDCDescriptorSubtypes.HEADER),
+    "bcdCDC"              / DescriptorField(description="CDC Version", default=1.1)
+)
+
+ACMFunctionalDescriptor = DescriptorFormat(
+    "bLength"             / construct.Const(4, construct.Int8ul),
+    "bDescriptorType"     / DescriptorNumber(CDCDescriptorNumbers.CS_INTERFACE),
+    "bDescriptorSubtype"  / DescriptorNumber(CDCDescriptorSubtypes.ABSTRACT_CONTROL_MANAGEMENT_FUNCTIONAL),
+    "bmCapabilities"      / DescriptorField(description="ACM Capabilities", default=0b0010)
+)
+
+UnionFunctionalDescriptor = DescriptorFormat(
+    "bLength"                / construct.Const(5, construct.Int8ul),
+    "bDescriptorType"        / DescriptorNumber(CDCDescriptorNumbers.CS_INTERFACE),
+    "bDescriptorSubtype"     / DescriptorNumber(CDCDescriptorSubtypes.UNION_FUNCTIONAL_DESCRIPTOR),
+    "bControlInterface"      / DescriptorField(description="Control Interface Number"),
+    "bSubordinateInterface0" / DescriptorField(description="Subordinate Interface Number")
+)
+
+CallManagementFunctionalDescriptor = DescriptorFormat(
+    "bLength"                / construct.Const(5, construct.Int8ul),
+    "bDescriptorType"        / DescriptorNumber(CDCDescriptorNumbers.CS_INTERFACE),
+    "bDescriptorSubtype"     / DescriptorNumber(CDCDescriptorSubtypes.CALL_MANAGEMENT_FUNCTIONAL),
+    "bmCapabilities"         / DescriptorField(description="Call Management capabilities", default=0),
+    "bDataInterface"         / DescriptorField(description="Data Interface Number")
+)