diff --git a/book/source/17a-adv-certificates.md b/book/source/17a-adv-certificates.md
index 2de12e9..a49ba9d 100644
--- a/book/source/17a-adv-certificates.md
+++ b/book/source/17a-adv-certificates.md
@@ -353,7 +353,7 @@ The KOO keyserver was designed to:
 1. conform to [GDPR regulations](https://en.wikipedia.org/wiki/General_Data_Protection_Regulation), and
 2. be resistant to flooding-style vandalism.
  
-To achieve these goals, KOO does not serve identitiy components at all, unless an explicit opt-in has been performed, using a confirmation process vial email. Third-party certifications are also not served by default, but only under very specific circumstances, which preclude flooding.
+To achieve these goals, KOO does not serve identity components at all, unless an explicit opt-in has been performed, using a confirmation process vial email. Third-party certifications are also not served by default, but only under very specific circumstances, which preclude flooding.
 ```
 
 ### Hockeypuck-based keyservers