diff --git a/integresql_client_python/__init__.py b/integresql_client_python/__init__.py
index 207b578..8f1891b 100644
--- a/integresql_client_python/__init__.py
+++ b/integresql_client_python/__init__.py
@@ -2,6 +2,7 @@
 
 import hashlib
 import http.client
+import json
 import os
 import pathlib
 import sys
@@ -237,11 +238,13 @@ def request(self, method: str, path: str, *,
     ) -> requests.Response:
         path = path.lstrip('/')
         url = f"{self.base_url}/{self.api_version}/{path}"
+        headers = {"content-type": "application/json"}
+        json_payload = json.dumps(payload)
 
         if self.debug:
-            print(f"Request {method.upper()} to {url} with qs {qs} and data {payload}", file=sys.stderr)
+            print(f"Request {method.upper()} to {url} with qs {qs} and headers {headers} and data {json_payload}", file=sys.stderr)
 
-        rsp = self.connection.request(method, url, qs, payload)
+        rsp = self.connection.request(method, url, qs, json_payload, headers=headers)
 
         if self.debug:
             print(f"Response from {method.upper()} {url}: [{rsp.status_code}] {rsp.content}", file=sys.stderr)