diff --git a/nest_frontend/components/base/Button.module.css b/nest_frontend/components/base/Button.module.css
index e8e3f9a..9afa1d0 100644
--- a/nest_frontend/components/base/Button.module.css
+++ b/nest_frontend/components/base/Button.module.css
@@ -11,12 +11,6 @@
     cursor: pointer;
 }
 
-.Button[disabled] {
-    opacity: 0.5;
-
-    cursor: not-allowed;
-}
-
 .Button:focus-visible {
     outline: 4px solid var(--outline);
 }
diff --git a/nest_frontend/components/base/summary/SummaryLeft.js b/nest_frontend/components/base/summary/SummaryLeft.js
index 6ece72c..c9070b9 100644
--- a/nest_frontend/components/base/summary/SummaryLeft.js
+++ b/nest_frontend/components/base/summary/SummaryLeft.js
@@ -4,11 +4,18 @@ import classNames from "classnames"
 import { FontAwesomeIcon } from "@fortawesome/react-fontawesome"
 
 
-export default function SummaryLeft({ icon, title, subtitle, className, onClick, ...props }) {
+export default function SummaryLeft({ icon, title, subtitle, className, onClick, disabled, ...props }) {
+    const _onClick = disabled ? null : onClick
+
     return (
         <div
-            className={classNames(Style.SummaryLeft, onClick ? "Clickable" : null, className)}
-            onClick={onClick}
+            className={classNames(
+                Style.SummaryLeft,
+                onClick ? "Clickable" : null,
+                (onClick && disabled) ? "Disabled" : null,
+                className
+            )}
+            onClick={_onClick}
             {...props}
         >
             <div className={Style.IconContainer}>
diff --git a/nest_frontend/components/interactive/BoxUserList.js b/nest_frontend/components/interactive/BoxUserList.js
index 4f18b1b..093f86b 100644
--- a/nest_frontend/components/interactive/BoxUserList.js
+++ b/nest_frontend/components/interactive/BoxUserList.js
@@ -9,13 +9,15 @@ import ContextLanguage from "../../contexts/ContextLanguage"
  * A {@link BoxFullScrollable} rendering an array of users as {@link SummaryUser}s.
  *
  * @param users - Array of users to render.
+ * @param shareWithUser - Async function to share a repository with an user, to be passed to {@link SummaryUser}.
+ * @param unshareWithUser - Async function to unshare a repository with an user, to be passed to {@link SummaryUser}.
  * @param destroyUser - Async function to destroy an user, to be passed to {@link SummaryUser}.
  * @param running - Whether another request is currently running.
  * @param props - Additional props to pass to the box.
  * @returns {JSX.Element}
  * @constructor
  */
-export default function BoxUserList({ users, destroyUser, running, ...props }) {
+export default function BoxUserList({ users, shareWithUser, unshareWithUser, destroyUser, running, ...props }) {
     const { strings } = useContext(ContextLanguage)
 
     let contents
@@ -23,8 +25,17 @@ export default function BoxUserList({ users, destroyUser, running, ...props }) {
         contents = <Loading/>
     }
     else {
-        contents = users.map(user =>
-            <SummaryUser key={user["email"]} destroyUser={destroyUser} running={running} user={user}/>)
+        contents = users.map(user => (
+                <SummaryUser
+                    key={user["email"]}
+                    shareWithUser={shareWithUser}
+                    unshareWithUser={unshareWithUser}
+                    destroyUser={destroyUser}
+                    running={running}
+                    user={user}
+                />
+            )
+        )
     }
 
     return (
diff --git a/nest_frontend/components/interactive/SummaryRepository.js b/nest_frontend/components/interactive/SummaryRepository.js
index 2add0a4..75ba44e 100644
--- a/nest_frontend/components/interactive/SummaryRepository.js
+++ b/nest_frontend/components/interactive/SummaryRepository.js
@@ -35,6 +35,7 @@ export default function SummaryRepository(
                 title={repo.name}
                 subtitle={repo.owner ? repo.owner.username : null}
                 onClick={view}
+                disabled={running}
             />
 
             <SummaryLabels
diff --git a/nest_frontend/components/interactive/SummaryUser.js b/nest_frontend/components/interactive/SummaryUser.js
index 0124205..ebe42eb 100644
--- a/nest_frontend/components/interactive/SummaryUser.js
+++ b/nest_frontend/components/interactive/SummaryUser.js
@@ -1,24 +1,27 @@
 import React, { useContext } from "react"
-import { faStar, faTrash, faUser } from "@fortawesome/free-solid-svg-icons"
+import { faShare, faStar, faTrash, faUser } from "@fortawesome/free-solid-svg-icons"
 import ContextLanguage from "../../contexts/ContextLanguage"
 import SummaryBase from "../base/summary/SummaryBase"
 import SummaryLeft from "../base/summary/SummaryLeft"
 import SummaryLabels from "../base/summary/SummaryLabels"
 import SummaryButton from "../base/summary/SummaryButton"
 import SummaryRight from "../base/summary/SummaryRight"
+import {FontAwesomeIcon} from "@fortawesome/react-fontawesome"
 
 
 /**
  * A {@link SummaryBase} representing a N.E.S.T. user.
  *
  * @param user - The user to represent.
+ * @param shareWithUser - Async function to share a repository with an user, to be passed to {@link SummaryUser}.
+ * @param unshareWithUser - Async function to unshare a repository with an user, to be passed to {@link SummaryUser}.
  * @param destroyUser - Async function <string> to destroy an user from the frontend.
  * @param running - Whether another request is already running.
  * @param props - Additional props to pass to the summary.
  * @returns {JSX.Element}
  * @constructor
  */
-export default function SummaryUser({ user, destroyUser, running, ...props }) {
+export default function SummaryUser({ user, shareWithUser, unshareWithUser, destroyUser, running, ...props }) {
     const { strings } = useContext(ContextLanguage)
 
     return (
@@ -27,23 +30,52 @@ export default function SummaryUser({ user, destroyUser, running, ...props }) {
                 icon={user.isAdmin ? faStar : faUser}
                 title={user.username}
                 subtitle={user.email}
+                disabled={running}
             />
             <SummaryLabels
                 upperLabel={strings.type}
                 upperValue={user.isAdmin ? strings.admin : strings.user}
             />
-            <SummaryButton
-                color={"Red"}
-                icon={faTrash}
-                onClick={async event => {
-                    event.stopPropagation()
-                    // TODO: Errors are not caught here. Where should they be displayed?
-                    await destroyUser(user["email"])
-                }}
-                disabled={running}
-            >
-                {strings.delete}
-            </SummaryButton>
+            {shareWithUser ?
+             <SummaryButton
+                 color={"Green"}
+                 icon={faShare}
+                 onClick={async event => {
+                     event.stopPropagation()
+                     await shareWithUser(user)
+                 }}
+                 disabled={running}
+             >
+                 {strings.share}
+             </SummaryButton>
+                         : null}
+            {unshareWithUser ?
+             <SummaryButton
+                 color={"Red"}
+                 icon={<FontAwesomeIcon icon={faShare} flip={"horizontal"}/>}
+                 onClick={async event => {
+                     event.stopPropagation()
+                     await unshareWithUser(user)
+                 }}
+                 disabled={running}
+             >
+                 {strings.unshare}
+             </SummaryButton>
+                         : null}
+            {destroyUser ?
+             <SummaryButton
+                 color={"Red"}
+                 icon={faTrash}
+                 onClick={async event => {
+                     event.stopPropagation()
+                     // TODO: Errors are not caught here. Where should they be displayed?
+                     await destroyUser(user["email"])
+                 }}
+                 disabled={running}
+             >
+                 {strings.delete}
+             </SummaryButton>
+            : null}
             <SummaryRight/>
         </SummaryBase>
     )
diff --git a/nest_frontend/index.css b/nest_frontend/index.css
index 840c96b..861df53 100644
--- a/nest_frontend/index.css
+++ b/nest_frontend/index.css
@@ -24,8 +24,9 @@ h1, h2, h3, h4, h5, h6 {
     font-family: var(--font-title);
 }
 
-*[disabled] {
-    cursor: not-allowed;
+*[disabled], .Disabled {
+    opacity: 0.5;
+    cursor: not-allowed !important;
 }
 
 a {
diff --git a/nest_frontend/routes/PageShare.js b/nest_frontend/routes/PageShare.js
index acbab77..404f33f 100644
--- a/nest_frontend/routes/PageShare.js
+++ b/nest_frontend/routes/PageShare.js
@@ -1,18 +1,76 @@
-import React, { useContext } from "react"
+import React, { useCallback, useContext } from "react"
 import classNames from "classnames"
 import BoxHeader from "../components/base/BoxHeader"
 import ContextLanguage from "../contexts/ContextLanguage"
 import Style from "./PageShare.module.css"
+import BoxUserList from "../components/interactive/BoxUserList"
+import useBackendViewset from "../hooks/useBackendViewset"
+import { useParams } from "react-router"
 
 
 export default function PageShare({ className, ...props }) {
     const { strings } = useContext(ContextLanguage)
+    const { id } = useParams()
+    const {resources: users} = useBackendViewset(
+        "/api/v1/users/",
+        "email",
+        {
+            list: true,
+            create: false,
+            retrieve: false,
+            edit: false,
+            destroy: false,
+            command: false,
+            action: false,
+        }
+    )
+    const {resources: authorizations, createResource: createAuthorization, destroyResource: destroyAuthorization} = useBackendViewset(
+        `/api/v1/repositories/${id}/authorizations/`,
+        "email",
+        {
+            list: true,
+            create: true,
+            retrieve: false,
+            edit: false,
+            destroy: true,
+            command: false,
+            action: false,
+        }
+    )
+
+    const shareWith = useCallback(
+        user => {
+            console.info("Authorizing ", user, " ...")
+            createAuthorization({rid: id, email: user.email})
+        },
+        [createAuthorization, id]
+    )
+
+    const unshareWith = useCallback(
+        user => {
+            console.info("Deauthorizing ", user, " ...")
+            destroyAuthorization(user.email)
+        },
+        [destroyAuthorization, id]
+    )
 
     return (
         <div className={classNames(Style.PageShare, className)} {...props}>
             <BoxHeader className={Style.Header}>
                 {strings.repoShare}
             </BoxHeader>
+            <BoxUserList
+                className={Style.UserList}
+                users={users.filter(user => !authorizations.map(a => a.email).includes(user.email))}
+                shareWithUser={shareWith}
+                header={strings.availableUsers}
+            />
+            <BoxUserList
+                className={Style.SharingWith}
+                users={users.filter(user => authorizations.map(a => a.email).includes(user.email))}
+                unshareWithUser={unshareWith}
+                header={strings.sharingWith}
+            />
         </div>
     )
 }
diff --git a/nest_frontend/routes/PageShare.module.css b/nest_frontend/routes/PageShare.module.css
index e385935..f2b083e 100644
--- a/nest_frontend/routes/PageShare.module.css
+++ b/nest_frontend/routes/PageShare.module.css
@@ -1,3 +1,27 @@
 .PageShare {
+    display: grid;
 
+    grid-template-areas:
+        "a"
+        "b"
+        "c";
+    grid-template-rows: auto 1fr 1fr;
+    grid-template-columns: 1fr;
+    grid-gap: 10px;
+
+    width: 100%;
+    height: 100%;
+}
+
+
+.Header {
+    grid-area: a;
+}
+
+.UserList {
+    grid-area: b;
+}
+
+.SharingWith {
+    grid-area: c;
 }