diff --git a/central_frontend/src/api/DeviceApi.ts b/central_frontend/src/api/DeviceApi.ts
index 5024df9..4820405 100644
--- a/central_frontend/src/api/DeviceApi.ts
+++ b/central_frontend/src/api/DeviceApi.ts
@@ -12,8 +12,10 @@ export interface DailyMinRuntime {
   catch_up_hours: number[];
 }
 
+export type RelayID = string;
+
 export interface DeviceRelay {
-  id: string;
+  id: RelayID;
   name: string;
   enabled: boolean;
   priority: number;
@@ -21,8 +23,8 @@ export interface DeviceRelay {
   minimal_uptime: number;
   minimal_downtime: number;
   daily_runtime?: DailyMinRuntime;
-  depends_on: DeviceRelay[];
-  conflicts_with: DeviceRelay[];
+  depends_on: RelayID[];
+  conflicts_with: RelayID[];
 }
 
 export interface Device {
diff --git a/central_frontend/src/api/RelayApi.ts b/central_frontend/src/api/RelayApi.ts
new file mode 100644
index 0000000..33f7546
--- /dev/null
+++ b/central_frontend/src/api/RelayApi.ts
@@ -0,0 +1,16 @@
+import { APIClient } from "./ApiClient";
+import { DeviceRelay } from "./DeviceApi";
+
+export class RelayApi {
+  /**
+   * Get the full list of relays
+   */
+  static async GetList(): Promise<DeviceRelay[]> {
+    return (
+      await APIClient.exec({
+        method: "GET",
+        uri: "/relays/list",
+      })
+    ).data;
+  }
+}
diff --git a/central_frontend/src/dialogs/EditDeviceRelaysDialog.tsx b/central_frontend/src/dialogs/EditDeviceRelaysDialog.tsx
index 1d3f898..c042692 100644
--- a/central_frontend/src/dialogs/EditDeviceRelaysDialog.tsx
+++ b/central_frontend/src/dialogs/EditDeviceRelaysDialog.tsx
@@ -17,8 +17,9 @@ import { useSnackbar } from "../hooks/context_providers/SnackbarProvider";
 import { dayjsToTimeOfDay, timeOfDay } from "../utils/DateUtils";
 import { lenValid } from "../utils/StringsUtils";
 import { CheckboxInput } from "../widgets/forms/CheckboxInput";
-import { TextInput } from "../widgets/forms/TextInput";
 import { MultipleSelectInput } from "../widgets/forms/MultipleSelectInput";
+import { SelectMultipleRelaysInput } from "../widgets/forms/SelectMultipleRelaysInput";
+import { TextInput } from "../widgets/forms/TextInput";
 
 export function EditDeviceRelaysDialog(p: {
   onClose: () => void;
@@ -270,6 +271,42 @@ export function EditDeviceRelaysDialog(p: {
             </>
           )}
         </Grid>
+
+        <DialogFormTitle>Constraints</DialogFormTitle>
+        <Grid container spacing={2}>
+          <Grid item xs={6}>
+            <SelectMultipleRelaysInput
+              label="Required relays"
+              exclude={[relay.id]}
+              value={relay.depends_on}
+              onValueChange={(v) =>
+                setRelay((r) => {
+                  return {
+                    ...r,
+                    depends_on: v,
+                  };
+                })
+              }
+              helperText="Relays that must be already up for this relay to be started"
+            />
+          </Grid>
+          <Grid item xs={6}>
+            <SelectMultipleRelaysInput
+              label="Conflicting relays"
+              exclude={[relay.id]}
+              value={relay.conflicts_with}
+              onValueChange={(v) =>
+                setRelay((r) => {
+                  return {
+                    ...r,
+                    conflicts_with: v,
+                  };
+                })
+              }
+              helperText="Relays that must be off before this relay can be started"
+            />
+          </Grid>
+        </Grid>
       </DialogContent>
       <DialogActions>
         <Button onClick={p.onClose}>Cancel</Button>
diff --git a/central_frontend/src/widgets/forms/SelectMultipleRelaysInput.tsx b/central_frontend/src/widgets/forms/SelectMultipleRelaysInput.tsx
new file mode 100644
index 0000000..adbcf0b
--- /dev/null
+++ b/central_frontend/src/widgets/forms/SelectMultipleRelaysInput.tsx
@@ -0,0 +1,44 @@
+import React from "react";
+import { DeviceRelay, RelayID } from "../../api/DeviceApi";
+import { RelayApi } from "../../api/RelayApi";
+import { AsyncWidget } from "../AsyncWidget";
+import { MultipleSelectInput } from "./MultipleSelectInput";
+
+export function SelectMultipleRelaysInput(p: {
+  label: string;
+  value: RelayID[];
+  onValueChange: (ids: RelayID[]) => void;
+  exclude?: RelayID[];
+  helperText?: string;
+}): React.ReactElement {
+  const [list, setList] = React.useState<DeviceRelay[]>();
+
+  const load = async () => {
+    setList(await RelayApi.GetList());
+  };
+
+  const values =
+    list?.map((r) => {
+      return {
+        label: r.name,
+        value: r.id,
+      };
+    }) ?? [];
+
+  return (
+    <AsyncWidget
+      loadKey={1}
+      load={load}
+      errMsg="Failed to load the list of relays!"
+      build={() => (
+        <MultipleSelectInput
+          label={p.label}
+          onChange={p.onValueChange}
+          selected={p.value}
+          helperText={p.helperText}
+          values={values}
+        />
+      )}
+    />
+  );
+}