diff --git a/CHANGES.txt b/CHANGES.txt
index 3e1d596..1f08ad2 100644
--- a/CHANGES.txt
+++ b/CHANGES.txt
@@ -28,6 +28,10 @@
 
     AVRO-504. ruby impl could stand better error messages on schema parsing (jmhodges)
 
+    AVRO-556. Poor performance for Reader::readBytes improved
+    (Dave Wright via sbanacho)
+
+
   BUG FIXES
     AVRO-461. Skipping primitives in the ruby side (jmhodges)
 
diff --git a/lang/c++/api/Reader.hh b/lang/c++/api/Reader.hh
index cdf14aa..be6c2d9 100644
--- a/lang/c++/api/Reader.hh
+++ b/lang/c++/api/Reader.hh
@@ -92,19 +92,12 @@
 
     void readBytes(std::vector<uint8_t> &val) {
         int64_t size = readSize();
-        
-        val.reserve(size);
-        uint8_t bval;
-        for(size_t bytes = 0; bytes < static_cast<size_t>(size); bytes++) {
-            in_.readByte(bval);
-            val.push_back(bval);
-        }
+        val.resize(size);
+        in_.readBytes(&val[0], size);
     }
 
     void readFixed(uint8_t *val, size_t size) {
-        for(size_t bytes = 0; bytes < size; bytes++) {
-            in_.readByte(val[bytes]);
-        }
+        in_.readBytes(val, size);
     }
 
     template <size_t N>