diff --git a/template/template.go b/template/template.go
index 3295544a..73035647 100644
--- a/template/template.go
+++ b/template/template.go
@@ -168,11 +168,14 @@ func (t *Template) ExecuteHTMLString(html string, data interface{}) (string, err
 type FuncMap map[string]interface{}
 
 var DefaultFuncs = FuncMap{
-	"toUpper":   strings.ToUpper,
-	"toLower":   strings.ToLower,
+	"toUpper": strings.ToUpper,
+	"toLower": strings.ToLower,
+	"title": func(text string) string {
+		// casers should not be shared between goroutines, instead
+		// create a new caser each time this function is called
+		return cases.Title(language.AmericanEnglish).String(text)
+	},
 	"trimSpace": strings.TrimSpace,
-
-	"title": cases.Title(language.AmericanEnglish).String,
 	// join is equal to strings.Join but inverts the argument order
 	// for easier pipelining in templates.
 	"join": func(sep string, s []string) string {
diff --git a/template/template_test.go b/template/template_test.go
index c28fa592..97d36fb1 100644
--- a/template/template_test.go
+++ b/template/template_test.go
@@ -16,6 +16,7 @@ package template
 import (
 	tmplhtml "html/template"
 	"net/url"
+	"sync"
 	"testing"
 	tmpltext "text/template"
 	"time"
@@ -465,3 +466,60 @@ func TestTemplateExpansionWithOptions(t *testing.T) {
 		})
 	}
 }
+
+// This test asserts that template functions are thread-safe.
+func TestTemplateFuncs(t *testing.T) {
+	tmpl, err := FromGlobs([]string{})
+	require.NoError(t, err)
+
+	for _, tc := range []struct {
+		title string
+		in    string
+		data  interface{}
+		exp   string
+	}{{
+		title: "Template using toUpper",
+		in:    `{{ "abc" | toUpper }}`,
+		exp:   "ABC",
+	}, {
+		title: "Template using toLower",
+		in:    `{{ "ABC" | toLower }}`,
+		exp:   "abc",
+	}, {
+		title: "Template using title",
+		in:    `{{ "abc" | title }}`,
+		exp:   "Abc",
+	}, {
+		title: "Template using trimSpace",
+		in:    `{{ " abc " | trimSpace }}`,
+		exp:   "abc",
+	}, {
+		title: "Template using join",
+		in:    `{{ . | join "," }}`,
+		data:  []string{"abc", "def"},
+		exp:   "abc,def",
+	}, {
+		title: "Template using match",
+		in:    `{{ match "[a-z]+" "abc" }}`,
+		exp:   "true",
+	}, {
+		title: "Template using reReplaceAll",
+		in:    `{{ reReplaceAll "ab" "AB" "abc" }}`,
+		exp:   "ABc",
+	}} {
+		tc := tc
+		t.Run(tc.title, func(t *testing.T) {
+			wg := sync.WaitGroup{}
+			for i := 0; i < 10; i++ {
+				wg.Add(1)
+				go func() {
+					defer wg.Done()
+					got, err := tmpl.ExecuteTextString(tc.in, tc.data)
+					require.NoError(t, err)
+					require.Equal(t, tc.exp, got)
+				}()
+			}
+			wg.Wait()
+		})
+	}
+}