diff --git a/app/src/main/java/com/etesync/syncadapter/ui/etebase/CollectionMembersFragment.kt b/app/src/main/java/com/etesync/syncadapter/ui/etebase/CollectionMembersFragment.kt
index 013515a7..721103cc 100644
--- a/app/src/main/java/com/etesync/syncadapter/ui/etebase/CollectionMembersFragment.kt
+++ b/app/src/main/java/com/etesync/syncadapter/ui/etebase/CollectionMembersFragment.kt
@@ -1,20 +1,32 @@
 package com.etesync.syncadapter.ui.etebase
 
+import android.app.Dialog
+import android.app.ProgressDialog
 import android.graphics.Color.parseColor
 import android.os.Bundle
 import android.view.LayoutInflater
 import android.view.View
 import android.view.ViewGroup
+import android.widget.CheckBox
+import android.widget.EditText
 import android.widget.TextView
+import androidx.appcompat.app.AlertDialog
+import androidx.fragment.app.DialogFragment
 import androidx.fragment.app.Fragment
 import androidx.fragment.app.activityViewModels
+import com.etebase.client.Utils
+import com.etebase.client.exceptions.EtebaseException
+import com.etebase.client.exceptions.NotFoundException
 import com.etesync.syncadapter.CachedCollection
 import com.etesync.syncadapter.Constants
 import com.etesync.syncadapter.R
 import com.etesync.syncadapter.resource.LocalCalendar
 import com.etesync.syncadapter.ui.BaseActivity
+import org.jetbrains.anko.doAsync
+import org.jetbrains.anko.uiThread
 
 class CollectionMembersFragment : Fragment() {
+    private val model: AccountViewModel by activityViewModels()
     private val collectionModel: CollectionViewModel by activityViewModels()
 
     override fun onCreateView(inflater: LayoutInflater, container: ViewGroup?, savedInstanceState: Bundle?): View? {
@@ -34,7 +46,7 @@ class CollectionMembersFragment : Fragment() {
 
     private fun initUi(inflater: LayoutInflater, v: View, cachedCollection: CachedCollection) {
         v.findViewById<View>(R.id.add_member).setOnClickListener {
-
+            addMemberClicked()
         }
 
         val meta = cachedCollection.meta
@@ -60,4 +72,75 @@ class CollectionMembersFragment : Fragment() {
 
         v.findViewById<View>(R.id.progressBar).visibility = View.GONE
     }
+
+    private fun addMemberClicked() {
+        val view = View.inflate(requireContext(), R.layout.add_member_fragment, null)
+        val dialog = AlertDialog.Builder(requireContext())
+                .setTitle(R.string.collection_members_add)
+                .setIcon(R.drawable.ic_account_add_dark)
+                .setPositiveButton(android.R.string.yes) { _, _ ->
+                    val username = view.findViewById<EditText>(R.id.username).text.toString()
+                    val readOnly = view.findViewById<CheckBox>(R.id.read_only).isChecked
+
+                    val frag = AddMemberFragment(model.value!!, collectionModel.value!!, username, if (readOnly) "ro" else "rw")
+                    frag.show(childFragmentManager, null)
+                }
+                .setNegativeButton(android.R.string.no) { _, _ -> }
+        dialog.setView(view)
+        dialog.show()
+    }
+}
+
+class AddMemberFragment(private val accountHolder: AccountHolder, private val cachedCollection: CachedCollection, private val username: String, private val accessLevel: String) : DialogFragment() {
+    override fun onCreateDialog(savedInstanceState: Bundle?): Dialog {
+        val progress = ProgressDialog(context)
+        progress.setTitle(R.string.collection_members_adding)
+        progress.setMessage(getString(R.string.please_wait))
+        progress.isIndeterminate = true
+        progress.setCanceledOnTouchOutside(false)
+        isCancelable = false
+
+        doAsync {
+            val invitationManager = accountHolder.etebase.invitationManager
+            try {
+                val profile = invitationManager.fetchUserProfile(username)
+                val fingerprint = Utils.prettyFingerprint(profile.pubkey)
+                uiThread {
+                    val view = LayoutInflater.from(context).inflate(R.layout.fingerprint_alertdialog, null)
+                    (view.findViewById<View>(R.id.body) as TextView).text = getString(R.string.trust_fingerprint_body, username)
+                    (view.findViewById<View>(R.id.fingerprint) as TextView).text = fingerprint
+                    AlertDialog.Builder(requireContext())
+                            .setIcon(R.drawable.ic_fingerprint_dark)
+                            .setTitle(R.string.trust_fingerprint_title)
+                            .setView(view)
+                            .setPositiveButton(android.R.string.ok) { _, _ ->
+                                doAsync {
+                                    try {
+                                        invitationManager.invite(cachedCollection.col, username, profile.pubkey, accessLevel)
+                                        uiThread { dismiss() }
+                                    } catch (e: EtebaseException) {
+                                        uiThread { handleError(e.localizedMessage) }
+                                    }
+                                }
+                            }
+                            .setNegativeButton(android.R.string.cancel) { _, _ -> dismiss() }.show()
+                }
+            } catch (e: NotFoundException) {
+                uiThread { handleError(getString(R.string.collection_members_error_user_not_found, username)) }
+            } catch (e: EtebaseException) {
+                uiThread { handleError(e.localizedMessage) }
+            }
+        }
+
+        return progress
+    }
+
+    private fun handleError(message: String) {
+        AlertDialog.Builder(requireContext())
+                .setIcon(R.drawable.ic_error_dark)
+                .setTitle(R.string.collection_members_add_error)
+                .setMessage(message)
+                .setPositiveButton(android.R.string.yes) { _, _ -> }.show()
+        dismiss()
+    }
 }
\ No newline at end of file
diff --git a/app/src/main/res/values/strings.xml b/app/src/main/res/values/strings.xml
index 0aa671b3..667b7373 100644
--- a/app/src/main/res/values/strings.xml
+++ b/app/src/main/res/values/strings.xml
@@ -161,7 +161,7 @@
     <string name="collection_members_adding">Adding member</string>
     <string name="trust_fingerprint_title">Verify security fingerprint</string>
     <string name="trust_fingerprint_body">Verify %s\'s security fingerprint to ensure the encryption is secure.</string>
-    <string name="collection_members_error_user_not_found">User (%s) not found. Have they setup their encryption password from one of the apps?</string>
+    <string name="collection_members_error_user_not_found">User (%s) not found</string>
     <string name="collection_members_removing">Removing member</string>
     <string name="collection_members_remove_error">Error removing member</string>
     <string name="collection_members_remove_title">Remove member</string>