diff --git a/packages/proto-signing/src/index.ts b/packages/proto-signing/src/index.ts
index c76ba594..fc518bfd 100644
--- a/packages/proto-signing/src/index.ts
+++ b/packages/proto-signing/src/index.ts
@@ -2,4 +2,5 @@ export { Coin } from "./msgs";
 export { cosmosField } from "./decorator";
 export { Registry } from "./registry";
 export { DirectSecp256k1Wallet } from "./directsecp256k1wallet";
+export { decodePubkey, encodePubkey } from "./pubkey";
 export { makeAuthInfo, makeSignBytes } from "./signing";
diff --git a/packages/proto-signing/src/pubkey.spec.ts b/packages/proto-signing/src/pubkey.spec.ts
new file mode 100644
index 00000000..09cccd27
--- /dev/null
+++ b/packages/proto-signing/src/pubkey.spec.ts
@@ -0,0 +1,54 @@
+/* eslint-disable @typescript-eslint/naming-convention */
+import { fromBase64 } from "@cosmjs/encoding";
+
+import { google } from "./codec";
+import { decodePubkey, encodePubkey } from "./pubkey";
+
+const { Any } = google.protobuf;
+
+describe("pubkey", () => {
+  const defaultPubkeyBase64 = "AtQaCqFnshaZQp6rIkvAPyzThvCvXSDO+9AzbxVErqJP";
+  const defaultPubkeyBytes = fromBase64(defaultPubkeyBase64);
+  const defaultPubkeyProtoBytes = Uint8Array.from([0x0a, defaultPubkeyBytes.length, ...defaultPubkeyBytes]);
+
+  describe("encodePubkey", () => {
+    it("works for secp256k1", () => {
+      const pubkey = { type: "tendermint/PubKeySecp256k1", value: defaultPubkeyBase64 };
+      expect(encodePubkey(pubkey)).toEqual(
+        Any.create({
+          type_url: "/cosmos.crypto.secp256k1.PubKey",
+          value: defaultPubkeyProtoBytes,
+        }),
+      );
+    });
+
+    it("throws for unsupported pubkey types", () => {
+      const pubkey = {
+        type: "tendermint/PubKeyUnknown",
+        value: defaultPubkeyBase64,
+      };
+      expect(() => encodePubkey(pubkey)).toThrowError(/not recognized/i);
+    });
+  });
+
+  describe("decodePubkey", () => {
+    it("works for secp256k1", () => {
+      const pubkey = {
+        type_url: "/cosmos.crypto.secp256k1.PubKey",
+        value: defaultPubkeyProtoBytes,
+      };
+      expect(decodePubkey(pubkey)).toEqual({
+        type: "tendermint/PubKeySecp256k1",
+        value: defaultPubkeyBase64,
+      });
+    });
+
+    it("throws for unsupported pubkey types", () => {
+      const pubkey = {
+        type_url: "/cosmos.crypto.unknown.PubKey",
+        value: defaultPubkeyProtoBytes,
+      };
+      expect(() => decodePubkey(pubkey)).toThrowError(/not recognized/i);
+    });
+  });
+});
diff --git a/packages/proto-signing/src/pubkey.ts b/packages/proto-signing/src/pubkey.ts
new file mode 100644
index 00000000..80da8019
--- /dev/null
+++ b/packages/proto-signing/src/pubkey.ts
@@ -0,0 +1,38 @@
+/* eslint-disable @typescript-eslint/naming-convention */
+import { fromBase64 } from "@cosmjs/encoding";
+import { encodeSecp256k1Pubkey, PubKey } from "@cosmjs/launchpad";
+
+import { cosmos, google } from "./codec";
+
+const { Any } = google.protobuf;
+
+export function encodePubkey(pubkey: PubKey): google.protobuf.IAny {
+  switch (pubkey.type) {
+    case "tendermint/PubKeySecp256k1": {
+      const pubkeyProto = cosmos.crypto.secp256k1.PubKey.create({
+        key: fromBase64(pubkey.value),
+      });
+      return Any.create({
+        type_url: "/cosmos.crypto.secp256k1.PubKey",
+        value: Uint8Array.from(cosmos.crypto.secp256k1.PubKey.encode(pubkeyProto).finish()),
+      });
+    }
+    default:
+      throw new Error(`Pubkey type ${pubkey.type} not recognized`);
+  }
+}
+
+export function decodePubkey(pubkey?: google.protobuf.IAny | null): PubKey | null {
+  if (!pubkey || !pubkey.value) {
+    return null;
+  }
+
+  switch (pubkey.type_url) {
+    case "/cosmos.crypto.secp256k1.PubKey": {
+      const { key } = cosmos.crypto.secp256k1.PubKey.decode(pubkey.value);
+      return encodeSecp256k1Pubkey(key);
+    }
+    default:
+      throw new Error(`Pubkey type_url ${pubkey.type_url} not recognized`);
+  }
+}
diff --git a/packages/proto-signing/types/index.d.ts b/packages/proto-signing/types/index.d.ts
index c76ba594..fc518bfd 100644
--- a/packages/proto-signing/types/index.d.ts
+++ b/packages/proto-signing/types/index.d.ts
@@ -2,4 +2,5 @@ export { Coin } from "./msgs";
 export { cosmosField } from "./decorator";
 export { Registry } from "./registry";
 export { DirectSecp256k1Wallet } from "./directsecp256k1wallet";
+export { decodePubkey, encodePubkey } from "./pubkey";
 export { makeAuthInfo, makeSignBytes } from "./signing";
diff --git a/packages/proto-signing/types/pubkey.d.ts b/packages/proto-signing/types/pubkey.d.ts
new file mode 100644
index 00000000..dcd790d1
--- /dev/null
+++ b/packages/proto-signing/types/pubkey.d.ts
@@ -0,0 +1,4 @@
+import { PubKey } from "@cosmjs/launchpad";
+import { google } from "./codec";
+export declare function encodePubkey(pubkey: PubKey): google.protobuf.IAny;
+export declare function decodePubkey(pubkey?: google.protobuf.IAny | null): PubKey | null;