diff --git a/publicsuffix/list.go b/publicsuffix/list.go
index 8405ac1..200617e 100644
--- a/publicsuffix/list.go
+++ b/publicsuffix/list.go
@@ -165,6 +165,10 @@
 // EffectiveTLDPlusOne returns the effective top level domain plus one more
 // label. For example, the eTLD+1 for "foo.bar.golang.org" is "golang.org".
 func EffectiveTLDPlusOne(domain string) (string, error) {
+	if strings.HasPrefix(domain, ".") || strings.HasSuffix(domain, ".") || strings.Contains(domain, "..") {
+		return "", fmt.Errorf("publicsuffix: empty label in domain %q", domain)
+	}
+
 	suffix, _ := PublicSuffix(domain)
 	if len(domain) <= len(suffix) {
 		return "", fmt.Errorf("publicsuffix: cannot derive eTLD+1 for domain %q", domain)
diff --git a/publicsuffix/list_test.go b/publicsuffix/list_test.go
index 98f8442..090c431 100644
--- a/publicsuffix/list_test.go
+++ b/publicsuffix/list_test.go
@@ -489,6 +489,14 @@
 	{"www.xn--85x722f.xn--fiqs8s", "xn--85x722f.xn--fiqs8s"},
 	{"shishi.xn--fiqs8s", "shishi.xn--fiqs8s"},
 	{"xn--fiqs8s", ""},
+
+	// Invalid input
+	{".", ""},
+	{"de.", ""},
+	{".de", ""},
+	{".com.au", ""},
+	{"com.au.", ""},
+	{"com..au", ""},
 }
 
 func TestEffectiveTLDPlusOne(t *testing.T) {