diff --git a/pkg/icingadb/v1/notification.go b/pkg/icingadb/v1/notification.go
index e3256ec5..a733605b 100644
--- a/pkg/icingadb/v1/notification.go
+++ b/pkg/icingadb/v1/notification.go
@@ -9,16 +9,16 @@ type Notification struct {
 	EntityWithChecksum   `json:",inline"`
 	EnvironmentMeta      `json:",inline"`
 	NameCiMeta           `json:",inline"`
-	HostId               types.Binary `json:"host_id"`
-	ServiceId            types.Binary `json:"service_id"`
-	CommandId            types.Binary `json:"command_id"`
-	TimesBegin           types.Int    `json:"times_begin"`
-	TimesEnd             types.Int    `json:"times_end"`
-	NotificationInterval uint32       `json:"notification_interval"`
-	TimeperiodId         types.Binary `json:"timeperiod_id"`
-	States               uint8        `json:"states"`
-	Types                uint16       `json:"types"`
-	ZoneId               types.Binary `json:"zone_id"`
+	HostId               types.Binary             `json:"host_id"`
+	ServiceId            types.Binary             `json:"service_id"`
+	CommandId            types.Binary             `json:"command_id"`
+	TimesBegin           types.Int                `json:"times_begin"`
+	TimesEnd             types.Int                `json:"times_end"`
+	NotificationInterval uint32                   `json:"notification_interval"`
+	TimeperiodId         types.Binary             `json:"timeperiod_id"`
+	States               types.NotificationStates `json:"states"`
+	Types                types.NotificationTypes  `json:"types"`
+	ZoneId               types.Binary             `json:"zone_id"`
 }
 
 type NotificationUser struct {
diff --git a/pkg/icingadb/v1/user.go b/pkg/icingadb/v1/user.go
index 96e61688..4bdf5b93 100644
--- a/pkg/icingadb/v1/user.go
+++ b/pkg/icingadb/v1/user.go
@@ -9,14 +9,14 @@ type User struct {
 	EntityWithChecksum   `json:",inline"`
 	EnvironmentMeta      `json:",inline"`
 	NameCiMeta           `json:",inline"`
-	DisplayName          string       `json:"display_name"`
-	Email                string       `json:"email"`
-	Pager                string       `json:"pager"`
-	NotificationsEnabled types.Bool   `json:"notifications_enabled"`
-	TimeperiodId         types.Binary `json:"timeperiod_id"`
-	States               uint8        `json:"states"`
-	Types                uint16       `json:"types"`
-	ZoneId               types.Binary `json:"zone_id"`
+	DisplayName          string                   `json:"display_name"`
+	Email                string                   `json:"email"`
+	Pager                string                   `json:"pager"`
+	NotificationsEnabled types.Bool               `json:"notifications_enabled"`
+	TimeperiodId         types.Binary             `json:"timeperiod_id"`
+	States               types.NotificationStates `json:"states"`
+	Types                types.NotificationTypes  `json:"types"`
+	ZoneId               types.Binary             `json:"zone_id"`
 }
 
 type UserCustomvar struct {
diff --git a/pkg/types/notification_states.go b/pkg/types/notification_states.go
new file mode 100644
index 00000000..ab3ce589
--- /dev/null
+++ b/pkg/types/notification_states.go
@@ -0,0 +1,76 @@
+package types
+
+import (
+	"database/sql/driver"
+	"encoding/json"
+	"fmt"
+)
+
+// NotificationStates specifies the set of states a notification may be sent for.
+type NotificationStates uint8
+
+// UnmarshalJSON implements the json.Unmarshaler interface.
+func (nst *NotificationStates) UnmarshalJSON(bytes []byte) error {
+	var states []string
+	if err := json.Unmarshal(bytes, &states); err != nil {
+		return err
+	}
+
+	var n NotificationStates
+	for _, state := range states {
+		if v, ok := notificationStateNames[state]; ok {
+			n |= v
+		} else {
+			return BadNotificationStates{states}
+		}
+	}
+
+	*nst = n
+	return nil
+}
+
+// Value implements the driver.Valuer interface.
+func (nst NotificationStates) Value() (driver.Value, error) {
+	if nst&^allNotificationStates == 0 {
+		return int64(nst), nil
+	} else {
+		return nil, BadNotificationStates{nst}
+	}
+}
+
+// BadNotificationStates complains about syntactically, but not semantically valid NotificationStates.
+type BadNotificationStates struct {
+	States interface{}
+}
+
+// Error implements the error interface.
+func (bns BadNotificationStates) Error() string {
+	return fmt.Sprintf("bad notification states: %#v", bns.States)
+}
+
+// notificationStateNames maps all valid NotificationStates values to their SQL representation.
+var notificationStateNames = map[string]NotificationStates{
+	"OK":       1,
+	"Warning":  2,
+	"Critical": 4,
+	"Unknown":  8,
+	"Up":       16,
+	"Down":     32,
+}
+
+// allNotificationStates is the largest valid NotificationStates value.
+var allNotificationStates = func() NotificationStates {
+	var nt NotificationStates
+	for _, v := range notificationStateNames {
+		nt |= v
+	}
+
+	return nt
+}()
+
+// Assert interface compliance.
+var (
+	_ error            = BadNotificationStates{}
+	_ json.Unmarshaler = (*NotificationStates)(nil)
+	_ driver.Valuer    = NotificationStates(0)
+)
diff --git a/pkg/types/notification_types.go b/pkg/types/notification_types.go
new file mode 100644
index 00000000..f6b8714f
--- /dev/null
+++ b/pkg/types/notification_types.go
@@ -0,0 +1,79 @@
+package types
+
+import (
+	"database/sql/driver"
+	"encoding/json"
+	"fmt"
+)
+
+// NotificationTypes specifies the set of reasons a notification may be sent for.
+type NotificationTypes uint16
+
+// UnmarshalJSON implements the json.Unmarshaler interface.
+func (nt *NotificationTypes) UnmarshalJSON(bytes []byte) error {
+	var types []string
+	if err := json.Unmarshal(bytes, &types); err != nil {
+		return err
+	}
+
+	var n NotificationTypes
+	for _, typ := range types {
+		if v, ok := notificationTypeNames[typ]; ok {
+			n |= v
+		} else {
+			return BadNotificationTypes{types}
+		}
+	}
+
+	*nt = n
+	return nil
+}
+
+// Value implements the driver.Valuer interface.
+func (nt NotificationTypes) Value() (driver.Value, error) {
+	if nt&^allNotificationTypes == 0 {
+		return int64(nt), nil
+	} else {
+		return nil, BadNotificationTypes{nt}
+	}
+}
+
+// BadNotificationTypes complains about syntactically, but not semantically valid NotificationTypes.
+type BadNotificationTypes struct {
+	Types interface{}
+}
+
+// Error implements the error interface.
+func (bnt BadNotificationTypes) Error() string {
+	return fmt.Sprintf("bad notification types: %#v", bnt.Types)
+}
+
+// notificationTypeNames maps all valid NotificationTypes values to their SQL representation.
+var notificationTypeNames = map[string]NotificationTypes{
+	"DowntimeStart":   1,
+	"DowntimeEnd":     2,
+	"DowntimeRemoved": 4,
+	"Custom":          8,
+	"Acknowledgement": 16,
+	"Problem":         32,
+	"Recovery":        64,
+	"FlappingStart":   128,
+	"FlappingEnd":     256,
+}
+
+// allNotificationTypes is the largest valid NotificationTypes value.
+var allNotificationTypes = func() NotificationTypes {
+	var nt NotificationTypes
+	for _, v := range notificationTypeNames {
+		nt |= v
+	}
+
+	return nt
+}()
+
+// Assert interface compliance.
+var (
+	_ error            = BadNotificationTypes{}
+	_ json.Unmarshaler = (*NotificationTypes)(nil)
+	_ driver.Valuer    = NotificationTypes(0)
+)