diff --git a/progress.md b/progress.md
index e64a4f1..4e72125 100644
--- a/progress.md
+++ b/progress.md
@@ -69,7 +69,7 @@
 - [x] Chapter 8: Goroutines and Channels
  - [x] 8.1 Goroutines
  - [x] 8.2 Example: Concurrent Clock Server
- - [ ] 8.3 Example: Concu rent Echo Server
+ - [x] 8.3 Example: Concu rent Echo Server
  - [ ] 8.4 Channels
  - [ ] 8.5 Looping in Parallel
  - [x] 8.6 Example: Concurrent Web Crawler