diff --git a/pipeline.go b/pipeline.go
index 8919210..b5697dc 100644
--- a/pipeline.go
+++ b/pipeline.go
@@ -197,12 +197,23 @@ func lowerStep(step Step, context *Context, stepContext *StepContext) (Step, err
 		return nil, err
 	}
 
+	name, ok := step["name"].(string)
+	if !ok {
+		name = ""
+	}
+	step["name"] = strings.TrimSpace(fmt.Sprintf(":%s: %s", stepContext.EmojiName, name))
+
+	// Block and wait steps must not contains agents or env, so we return early here
+	_, isBlockStep := step["block"]
+	_, isWaitStep := step["wait"]
+	if isBlockStep || isWaitStep {
+		return step, nil
+	}
+
 	agents, ok := step["agents"].(map[interface{}]interface{})
 	if !ok {
 		agents = make(map[interface{}]interface{})
-		if _, exists := step["wait"]; !exists {
-			step["agents"] = agents
-		}
+		step["agents"] = agents
 	}
 	agents["queue"] = stepContext.QueueName
 	agents["environment"] = stepContext.EnvironmentName
@@ -210,22 +221,15 @@ func lowerStep(step Step, context *Context, stepContext *StepContext) (Step, err
 	env, ok := step["env"].(map[interface{}]interface{})
 	if !ok {
 		env = make(map[interface{}]interface{})
-		if _, exists := step["wait"]; !exists {
-			step["env"] = env
-		}
+		step["env"] = env
 	}
+
 	env["JOBSWORTH_CAUTIOUS"] = stepContext.CautiousStr()
 	env["JOBSWORTH_CODEBASE"] = context.CodebaseName()
 	env["JOBSWORTH_CODE_VERSION"] = context.CodeVersion
 	env["JOBSWORTH_SOURCE_GIT_COMMIT_ID"] = context.SourceGitCommitId
 	env["JOBSWORTH_ENVIRONMENT"] = stepContext.EnvironmentName
 
-	name, ok := step["name"].(string)
-	if !ok {
-		name = ""
-	}
-	step["name"] = strings.TrimSpace(fmt.Sprintf(":%s: %s", stepContext.EmojiName, name))
-
 	if step["command"] != nil && stepContext.PreventConcurrency &&
 		step["concurrency"] == nil && step["concurrency_group"] == nil {
 		step["concurrency_group"] = fmt.Sprintf("%s/%s", stepContext.EnvironmentName, context.BuildkitePipelineSlug)
diff --git a/pipeline_test.go b/pipeline_test.go
index e2ae16d..d59df45 100644
--- a/pipeline_test.go
+++ b/pipeline_test.go
@@ -67,6 +67,29 @@ wait: ~
 	}
 }
 
+func TestBlockStep(t *testing.T) {
+	context := &Context{}
+	stepContext := &StepContext{}
+
+	step := Step{}
+	stepBytes := []byte(`
+block: ~
+name: "my block"
+if: 1 == 1
+`)
+	yaml.Unmarshal(stepBytes, &step)
+	step, err := lowerStep(step, context, stepContext)
+	if err != nil {
+		t.Error("lowerStep returned err:", err)
+	}
+	if !reflect.DeepEqual(step["env"], nil) {
+		t.Errorf("env should not be set for a block step")
+	}
+	if !reflect.DeepEqual(step["agents"], nil) {
+		t.Errorf("agents should not be set for a block step")
+	}
+}
+
 func TestInterpolate(t *testing.T) {
 	context := &Context{}
 	stepContext := &StepContext{