diff --git a/client/internal/clientstate.go b/client/internal/clientstate.go
index 95a04f81..7b67bdb2 100644
--- a/client/internal/clientstate.go
+++ b/client/internal/clientstate.go
@@ -32,6 +32,7 @@ var (
 // It is safe to call methods of this struct concurrently.
 type ClientSyncedState struct {
 	mutex sync.Mutex
+	packageSyncMutex sync.Mutex
 
 	agentDescription   *protobufs.AgentDescription
 	health             *protobufs.AgentHealth
diff --git a/client/internal/packagessyncer.go b/client/internal/packagessyncer.go
index 8f76a2cc..7a03a05b 100644
--- a/client/internal/packagessyncer.go
+++ b/client/internal/packagessyncer.go
@@ -6,6 +6,7 @@ import (
 	"errors"
 	"fmt"
 	"net/http"
+	"sync"
 
 	"github.com/open-telemetry/opamp-go/client/types"
 	"github.com/open-telemetry/opamp-go/protobufs"
@@ -58,7 +59,7 @@ func (s *packagesSyncer) Sync(ctx context.Context) error {
 	}
 
 	// Now do the actual syncing in the background.
-	go s.doSync(ctx)
+	go s.doSync(ctx, &s.clientSyncedState.packageSyncMutex)
 
 	return nil
 }
@@ -98,7 +99,7 @@ func (s *packagesSyncer) initStatuses() error {
 }
 
 // doSync performs the actual syncing process.
-func (s *packagesSyncer) doSync(ctx context.Context) {
+func (s *packagesSyncer) doSync(ctx context.Context, mutex *sync.Mutex) {
 	hash, err := s.localState.AllPackagesHash()
 	if err != nil {
 		s.logger.Errorf("Package syncing failed: %V", err)
@@ -109,6 +110,9 @@ func (s *packagesSyncer) doSync(ctx context.Context) {
 		return
 	}
 
+	(*mutex).Lock()
+	defer (*mutex).Unlock()
+
 	failed := false
 	if err := s.deleteUnneededLocalPackages(); err != nil {
 		s.logger.Errorf("Cannot delete unneeded packages: %v", err)