diff --git a/exercises/intergalactic-transmission/canonical-data.json b/exercises/intergalactic-transmission/canonical-data.json
new file mode 100644
index 000000000..f14035cad
--- /dev/null
+++ b/exercises/intergalactic-transmission/canonical-data.json
@@ -0,0 +1,440 @@
+{
+  "exercise": "intergalactic-transmission",
+  "comments": ["Inputs and expected data are given in hexadecimal"],
+  "cases": [
+    {
+      "description": "calculate transmit sequences",
+      "cases": [
+        {
+          "uuid": "f99d4046-b429-4582-9324-f0bcac7ab51c",
+          "description": "empty message",
+          "property": "transmitSequence",
+          "input": {
+            "message": []
+          },
+          "expected": []
+        },
+        {
+          "uuid": "ee27ea2d-8999-4f23-9275-8f6879545f86",
+          "description": "0x00 is transmitted as 0x0000",
+          "property": "transmitSequence",
+          "input": {
+            "message": ["0x00"]
+          },
+          "expected": ["0x00", "0x00"]
+        },
+        {
+          "uuid": "97f27f98-8020-402d-be85-f21ba54a6df0",
+          "description": "0x02 is transmitted as 0x0300",
+          "property": "transmitSequence",
+          "input": {
+            "message": ["0x02"]
+          },
+          "expected": ["0x03", "0x00"]
+        },
+        {
+          "uuid": "24712fb9-0336-4e2f-835e-d2350f29c420",
+          "description": "0x06 is transmitted as 0x0600",
+          "property": "transmitSequence",
+          "input": {
+            "message": ["0x06"]
+          },
+          "expected": ["0x06", "0x00"]
+        },
+        {
+          "uuid": "7630b5a9-dba1-4178-b2a0-4a376f7414e0",
+          "description": "0x05 is transmitted as 0x0581",
+          "property": "transmitSequence",
+          "input": {
+            "message": ["0x05"]
+          },
+          "expected": ["0x05", "0x81"]
+        },
+        {
+          "uuid": "ab4fe80b-ef8e-4a99-b4fb-001937af415d",
+          "description": "0x29 is transmitted as 0x2881",
+          "property": "transmitSequence",
+          "input": {
+            "message": ["0x29"]
+          },
+          "expected": ["0x28", "0x81"]
+        },
+        {
+          "uuid": "4e200d84-593b-4449-b7c0-4de1b6a0955e",
+          "description": "0xc001c0de is transmitted as 0xc000711be1",
+          "property": "transmitSequence",
+          "input": {
+            "message": ["0xc0", "0x01", "0xc0", "0xde"]
+          },
+          "expected": ["0xc0", "0x00", "0x71", "0x1b", "0xe1"]
+        },
+        {
+          "uuid": "fbc537e9-6b21-4f4a-8c2b-9cf9b702a9b7",
+          "description": "six byte message",
+          "property": "transmitSequence",
+          "input": {
+            "message": ["0x47", "0x72", "0x65", "0x61", "0x74", "0x21"]
+          },
+          "expected": ["0x47", "0xb8", "0x99", "0xac", "0x17", "0xa0", "0x84"]
+        },
+        {
+          "uuid": "d5b75adf-b5fc-4f77-b4ab-77653e30f07c",
+          "description": "seven byte message",
+          "comments": ["at 7 bytes long, no padding is required"],
+          "property": "transmitSequence",
+          "input": {
+            "message": ["0x47", "0x72", "0x65", "0x61", "0x74", "0x31", "0x21"]
+          },
+          "expected": [
+            "0x47",
+            "0xb8",
+            "0x99",
+            "0xac",
+            "0x17",
+            "0xa0",
+            "0xc5",
+            "0x42"
+          ]
+        },
+        {
+          "uuid": "6d8b297b-da1d-435e-bcd7-55fbb1400e73",
+          "description": "eight byte message",
+          "property": "transmitSequence",
+          "input": {
+            "message": [
+              "0xc0",
+              "0x01",
+              "0x13",
+              "0x37",
+              "0xc0",
+              "0xde",
+              "0x21",
+              "0x21"
+            ]
+          },
+          "expected": [
+            "0xc0",
+            "0x00",
+            "0x44",
+            "0x66",
+            "0x7d",
+            "0x06",
+            "0x78",
+            "0x42",
+            "0x21",
+            "0x81"
+          ]
+        },
+        {
+          "uuid": "54a0642a-d5aa-490c-be89-8e171a0cab6f",
+          "description": "twenty byte message",
+          "property": "transmitSequence",
+          "input": {
+            "message": [
+              "0x45",
+              "0x78",
+              "0x65",
+              "0x72",
+              "0x63",
+              "0x69",
+              "0x73",
+              "0x6d",
+              "0x20",
+              "0x69",
+              "0x73",
+              "0x20",
+              "0x61",
+              "0x77",
+              "0x65",
+              "0x73",
+              "0x6f",
+              "0x6d",
+              "0x65",
+              "0x21"
+            ]
+          },
+          "expected": [
+            "0x44",
+            "0xbd",
+            "0x18",
+            "0xaf",
+            "0x27",
+            "0x1b",
+            "0xa5",
+            "0xe7",
+            "0x6c",
+            "0x90",
+            "0x1b",
+            "0x2e",
+            "0x33",
+            "0x03",
+            "0x84",
+            "0xee",
+            "0x65",
+            "0xb8",
+            "0xdb",
+            "0xed",
+            "0xd7",
+            "0x28",
+            "0x84"
+          ]
+        }
+      ]
+    },
+    {
+      "description": "decode received messages",
+      "cases": [
+        {
+          "uuid": "9a8084dd-3336-474c-90cb-8a852524604d",
+          "description": "empty message",
+          "property": "decodeMessage",
+          "input": {
+            "message": []
+          },
+          "expected": []
+        },
+        {
+          "uuid": "879af739-0094-4736-9127-bd441b1ddbbf",
+          "description": "zero message",
+          "property": "decodeMessage",
+          "input": {
+            "message": ["0x00", "0x00"]
+          },
+          "expected": ["0x00"]
+        },
+        {
+          "uuid": "7a89eeef-96c5-4329-a246-ec181a8e959a",
+          "description": "0x0300 is decoded to 0x02",
+          "property": "decodeMessage",
+          "input": {
+            "message": ["0x03", "0x00"]
+          },
+          "expected": ["0x02"]
+        },
+        {
+          "uuid": "3e515af7-8b62-417f-960c-3454bca7f806",
+          "description": "0x0581 is decoded to 0x05",
+          "property": "decodeMessage",
+          "input": {
+            "message": ["0x05", "0x81"]
+          },
+          "expected": ["0x05"]
+        },
+        {
+          "uuid": "a1b4a3f7-9f05-4b7a-b86e-d7c6fc3f16a9",
+          "description": "0x2881 is decoded to 0x29",
+          "property": "decodeMessage",
+          "input": {
+            "message": ["0x28", "0x81"]
+          },
+          "expected": ["0x29"]
+        },
+        {
+          "uuid": "2e99d617-4c91-4ad5-9217-e4b2447d6e4a",
+          "description": "first byte has wrong parity",
+          "property": "decodeMessage",
+          "input": {
+            "message": ["0x07", "0x00"]
+          },
+          "expected": {
+            "error": "wrong parity"
+          }
+        },
+        {
+          "uuid": "507e212d-3dae-42e8-88b4-2223838ff8d2",
+          "description": "second byte has wrong parity",
+          "property": "decodeMessage",
+          "input": {
+            "message": ["0x03", "0x68"]
+          },
+          "expected": {
+            "error": "wrong parity"
+          }
+        },
+        {
+          "uuid": "b985692e-6338-46c7-8cea-bc38996d4dfd",
+          "description": "0xcf4b00 is decoded to 0xce94",
+          "property": "decodeMessage",
+          "input": {
+            "message": ["0xcf", "0x4b", "0x00"]
+          },
+          "expected": ["0xce", "0x94"]
+        },
+        {
+          "uuid": "7a1f4d48-696d-4679-917c-21b7da3ff3fd",
+          "description": "0xe2566500 is decoded to 0xe2ad90",
+          "property": "decodeMessage",
+          "input": {
+            "message": ["0xe2", "0x56", "0x65", "0x00"]
+          },
+          "expected": ["0xe2", "0xad", "0x90"]
+        },
+        {
+          "uuid": "467549dc-a558-443b-80c5-ff3d4eb305d4",
+          "description": "six byte message",
+          "property": "decodeMessage",
+          "input": {
+            "message": ["0x47", "0xb8", "0x99", "0xac", "0x17", "0xa0", "0x84"]
+          },
+          "expected": ["0x47", "0x72", "0x65", "0x61", "0x74", "0x21"]
+        },
+        {
+          "uuid": "1f3be5fb-093a-4661-9951-c1c4781c71ea",
+          "description": "seven byte message",
+          "property": "decodeMessage",
+          "input": {
+            "message": [
+              "0x47",
+              "0xb8",
+              "0x99",
+              "0xac",
+              "0x17",
+              "0xa0",
+              "0xc5",
+              "0x42"
+            ]
+          },
+          "expected": ["0x47", "0x72", "0x65", "0x61", "0x74", "0x31", "0x21"]
+        },
+        {
+          "uuid": "6065b8b3-9dcd-45c9-918c-b427cfdb28c1",
+          "description": "last byte has wrong parity",
+          "property": "decodeMessage",
+          "input": {
+            "message": [
+              "0x47",
+              "0xb8",
+              "0x99",
+              "0xac",
+              "0x17",
+              "0xa0",
+              "0xc5",
+              "0x43"
+            ]
+          },
+          "expected": {
+            "error": "wrong parity"
+          }
+        },
+        {
+          "uuid": "98af97b7-9cca-4c4c-9de3-f70e227a4cb1",
+          "description": "eight byte message",
+          "property": "decodeMessage",
+          "input": {
+            "message": [
+              "0xc0",
+              "0x00",
+              "0x44",
+              "0x66",
+              "0x7d",
+              "0x06",
+              "0x78",
+              "0x42",
+              "0x21",
+              "0x81"
+            ]
+          },
+          "expected": [
+            "0xc0",
+            "0x01",
+            "0x13",
+            "0x37",
+            "0xc0",
+            "0xde",
+            "0x21",
+            "0x21"
+          ]
+        },
+        {
+          "uuid": "aa7d4785-2bb9-43a4-a38a-203325c464fb",
+          "description": "twenty byte message",
+          "property": "decodeMessage",
+          "input": {
+            "message": [
+              "0x44",
+              "0xbd",
+              "0x18",
+              "0xaf",
+              "0x27",
+              "0x1b",
+              "0xa5",
+              "0xe7",
+              "0x6c",
+              "0x90",
+              "0x1b",
+              "0x2e",
+              "0x33",
+              "0x03",
+              "0x84",
+              "0xee",
+              "0x65",
+              "0xb8",
+              "0xdb",
+              "0xed",
+              "0xd7",
+              "0x28",
+              "0x84"
+            ]
+          },
+          "expected": [
+            "0x45",
+            "0x78",
+            "0x65",
+            "0x72",
+            "0x63",
+            "0x69",
+            "0x73",
+            "0x6d",
+            "0x20",
+            "0x69",
+            "0x73",
+            "0x20",
+            "0x61",
+            "0x77",
+            "0x65",
+            "0x73",
+            "0x6f",
+            "0x6d",
+            "0x65",
+            "0x21"
+          ]
+        },
+        {
+          "uuid": "4c86e034-b066-42ac-8497-48f9bc1723c1",
+          "description": "wrong parity on 16th byte",
+          "property": "decodeMessage",
+          "input": {
+            "message": [
+              "0x44",
+              "0xbd",
+              "0x18",
+              "0xaf",
+              "0x27",
+              "0x1b",
+              "0xa5",
+              "0xe7",
+              "0x6c",
+              "0x90",
+              "0x1b",
+              "0x2e",
+              "0x33",
+              "0x03",
+              "0x84",
+              "0xef",
+              "0x65",
+              "0xb8",
+              "0xdb",
+              "0xed",
+              "0xd7",
+              "0x28",
+              "0x84"
+            ]
+          },
+          "expected": {
+            "error": "wrong parity"
+          }
+        }
+      ]
+    }
+  ]
+}
diff --git a/exercises/intergalactic-transmission/instructions.md b/exercises/intergalactic-transmission/instructions.md
new file mode 100644
index 000000000..63fe661e0
--- /dev/null
+++ b/exercises/intergalactic-transmission/instructions.md
@@ -0,0 +1,54 @@
+# Instructions
+
+Your job is to help implement
+
+- the transmitter, which calculates the transmission sequence, and
+- the receiver, which decodes it.
+
+A parity bit is simple way of detecting transmission errors.
+The transmitters and receivers can only transmit and receive _exactly_ eight bits at a time (including the parity bit).
+The parity bit is set so that there is an _even_ number 1s in each transmission and is always the first bit from the right.
+So if the receiver receives `11000001`, `01110101` or `01000000` (i.e. a transmission with an odd number of 1 bits), it knows there is an error.
+
+However, messages are rarely this short, and need to be transmitted in a sequence when they are longer.
+
+For example, consider the message `11000000 00000001 11000000 11011110` (or `C0 01 C0 DE` in hex).
+
+Since each transmission contains exactly eight bits, it can only contain seven bits of data and the parity bit.
+A parity bit must then be inserted after every seven bits of data:
+
+```text
+11000000 00000001 11000000 11011110
+      ↑       ↑       ↑       ↑          (7th bits)
+```
+
+The transmission sequence for this message looks like this:
+
+```text
+1100000_ 0000000_ 0111000_ 0001101_ 1110
+       ↑        ↑        ↑        ↑      (parity bits)
+```
+
+The data in the first transmission in the sequence (`1100000`) has two 1 bits (an even number), so the parity bit is 0.
+The first transmission becomes `11000000` (or `C0` in hex).
+
+The data in the next transmission (`0000000`) has zero 1 bits (an even number again), so the parity bit is 0 again.
+The second transmission thus becomes `00000000` (or `00` in hex).
+
+The data for the next two transmissions (`0111000` and `0001101`) have three 1 bits.
+Their parity bits are set to 1 so that they have an even number of 1 bits in the transmission.
+They are transmitted as `01110001` and `00011011` (or `71` and `1B` in hex).
+
+The last transmission (`1110`) has only four bits of data.
+Since exactly eight bits are transmitted at a time and the parity bit is the right most bit, three 0 bits and then the parity bit are added to make up eight bits.
+It now looks like this (where `_` is the parity bit):
+
+```text
+1110 000_
+     ↑↑↑   (added 0 bits)
+```
+
+There is an odd number of 1 bits again, so the parity bit is 1.
+The last transmission in the sequence becomes `11100001` (or `E1` in hex).
+
+The entire transmission sequence for this message is `11000000 00000000 01110001 00011011 11100001` (or `C0 00 71 1B E1` in hex).
diff --git a/exercises/intergalactic-transmission/introduction.md b/exercises/intergalactic-transmission/introduction.md
new file mode 100644
index 000000000..f19dffbea
--- /dev/null
+++ b/exercises/intergalactic-transmission/introduction.md
@@ -0,0 +1,23 @@
+# Introduction
+
+Trillions upon trillions of messages zip between Earth and neighboring galaxies every millisecond.
+But transmitting over such long distances is tricky.
+Pesky solar flares, temporal distortions, stray forces, and even the flap of a space butterfly's wing can cause a random bit to change during transmission.
+
+Now imagine the consequences:
+
+- Crashing the Intergalactic Share Market when "buy low" turns to "sell now".
+- Losing contact with the Kepler Whirl system when "save new worm hole" becomes "cave new worm hole".
+- Or plunging the universe into existential horror by replacing a cowboy emoji 🤠 with a clown emoji 🤡.
+
+Detecting corrupted messages isn't just important — it's critical.
+The receiver _must_ know when something has gone wrong before disaster strikes.
+
+But how?
+Scientists and engineers from across the universe have been battling this problem for eons.
+Entire cosmic AI superclusters churn through the data.
+And then, one day, a legend resurfaces — an ancient, powerful method, whispered in debugging forums, muttered by engineers who've seen too much...
+
+The Parity Bit!
+
+A method so simple, so powerful, that it might just save interstellar communication.
diff --git a/exercises/intergalactic-transmission/metadata.toml b/exercises/intergalactic-transmission/metadata.toml
new file mode 100644
index 000000000..278a2843d
--- /dev/null
+++ b/exercises/intergalactic-transmission/metadata.toml
@@ -0,0 +1,4 @@
+title = "Intergalactic Transmission"
+blurb = "Add parity bits to a message for transmission"
+source = "Kah Goh"
+source_url = "https://github.com/exercism/problem-specifications/pull/2543"