diff --git a/.sprinkler.yaml b/.sprinkler.yaml
index 9a8994a..831ec62 100644
--- a/.sprinkler.yaml
+++ b/.sprinkler.yaml
@@ -18,6 +18,7 @@ control:
 
 scheduler:
   interval: "1s"
+  lockTimeout: "1h"
   orchard:
     address: "http://ws:8082"
     # apiKeyName: "x-api-key"
diff --git a/cmd/scheduler.go b/cmd/scheduler.go
index a1a03b7..dfdd8f7 100644
--- a/cmd/scheduler.go
+++ b/cmd/scheduler.go
@@ -14,7 +14,9 @@ import (
 )
 
 type SchedulerCmdOpt struct {
-	Interval          time.Duration
+	Interval    time.Duration
+	LockTimeout time.Duration
+
 	OrchardAddress    string
 	OrchardAPIKeyName string
 	OrchardAPIKey     string
@@ -26,6 +28,7 @@ func getSchedulerCmdOpt() SchedulerCmdOpt {
 		OrchardAddress:    viper.GetString("scheduler.orchard.address"),
 		OrchardAPIKeyName: viper.GetString("scheduler.orchard.apiKeyName"),
 		OrchardAPIKey:     viper.GetString("scheduler.orchard.apiKey"),
+		LockTimeout:       viper.GetDuration("scheduler.lockTimeout"),
 	}
 }
 
@@ -47,6 +50,7 @@ to quickly create a Cobra application.`,
 			OrchardHost:       schedulerCmdOpt.OrchardAddress,
 			OrchardAPIKeyName: schedulerCmdOpt.OrchardAPIKeyName,
 			OrchardAPIKey:     schedulerCmdOpt.OrchardAPIKey,
+			LockTimeout:       schedulerCmdOpt.LockTimeout,
 		}
 		scheduler.Start()
 	},
@@ -82,4 +86,11 @@ func init() {
 		"api key to orchard service",
 	)
 	viper.BindPFlag("scheduler.orchard.apiKey", schedulerCmd.Flags().Lookup("orchard"))
+
+	schedulerCmd.Flags().Duration(
+		"lockTimeout",
+		time.Hour,
+		"Workflow schedule and activation lock TTL",
+	)
+	viper.BindPFlag("scheduler.lockTimeout", schedulerCmd.Flags().Lookup("lockTimeout"))
 }
diff --git a/service/scheduler.go b/service/scheduler.go
index a4ff539..8852899 100644
--- a/service/scheduler.go
+++ b/service/scheduler.go
@@ -55,6 +55,7 @@ func (s ScheduleStatus) ToString() string {
 
 type Scheduler struct {
 	Interval          time.Duration
+	LockTimeout       time.Duration
 	MaxSize           uint
 	OrchardHost       string
 	OrchardAPIKeyName string
@@ -66,11 +67,24 @@ func (s *Scheduler) Start() {
 	tick := time.Tick(s.Interval)
 	for range tick {
 		fmt.Println("tick")
+		s.deleteExpiredLocks(database.GetInstance())
 		s.scheduleWorkflows(database.GetInstance())
 		s.activateWorkflows(database.GetInstance())
 	}
 }
 
+func (s *Scheduler) deleteExpiredLocks(db *gorm.DB) {
+	expiryTime := time.Now().Add(-s.LockTimeout)
+
+	db.Model(&table.WorkflowActivatorLock{}).
+		Where("lock_time < ?", expiryTime).
+		Delete(&table.WorkflowActivatorLock{})
+
+	db.Model(&table.WorkflowSchedulerLock{}).
+		Where("lock_time < ?", expiryTime).
+		Delete(&table.WorkflowSchedulerLock{})
+}
+
 func (s *Scheduler) scheduleWorkflows(db *gorm.DB) {
 	var workflows []table.Workflow
 
@@ -187,6 +201,10 @@ func (s *Scheduler) lockAndCreate(db *gorm.DB, wf table.Workflow) {
 		return
 	}
 
+	// release the lock
+	defer db.Where("workflow_id = ? and token = ?", wf.ID, token).
+		Delete(&table.WorkflowSchedulerLock{})
+
 	fmt.Println("creating workflow", wf.Name, token)
 	client := &orchard.OrchardRestClient{
 		Host:       s.OrchardHost,
@@ -221,10 +239,6 @@ func (s *Scheduler) lockAndCreate(db *gorm.DB, wf table.Workflow) {
 		}
 		return nil
 	})
-
-	// release the lock
-	db.Where("workflow_id = ? and token = ?", wf.ID, token).
-		Delete(&table.WorkflowSchedulerLock{})
 }
 
 func (s *Scheduler) lockAndActivate(db *gorm.DB, swf table.ScheduledWorkflow) {
@@ -249,6 +263,10 @@ func (s *Scheduler) lockAndActivate(db *gorm.DB, swf table.ScheduledWorkflow) {
 		return
 	}
 
+	// release the lock
+	defer db.Where("scheduled_id = ? and token = ?", swf.ID, token).
+		Delete(&table.WorkflowActivatorLock{})
+
 	fmt.Println("activating workflow", swf.OrchardID, token)
 	client := &orchard.OrchardRestClient{
 		Host:       s.OrchardHost,
@@ -268,10 +286,6 @@ func (s *Scheduler) lockAndActivate(db *gorm.DB, swf table.ScheduledWorkflow) {
 		}
 		return nil
 	})
-
-	// release the lock
-	db.Where("scheduled_id = ? and token = ?", swf.ID, token).
-		Delete(&table.WorkflowActivatorLock{})
 }
 
 func notifyOwner(wf table.Workflow, orchardErr error) {