diff --git a/app/controllers/invitations_controller.rb b/app/controllers/invitations_controller.rb
index 0ff0e23..b2cc6a4 100644
--- a/app/controllers/invitations_controller.rb
+++ b/app/controllers/invitations_controller.rb
@@ -5,14 +5,14 @@ def show
   end
 
   def accept
-    # find invitation by token
-    # invitation.accept
-    # redirect to invitation.html_url
+    @invitation = Invitation.find_by_token(params[:token])
+    invitation.accept!
+    redirect_to invitation_path(@invitation.token)
   end
 
   def reject
-    # find invitation by token
-    # invitation.reject
-    # redirect back invitation.html_url
+    @invitation = Invitation.find_by_token(params[:token])
+    invitation.reject!
+    redirect_to invitation_path(@invitation.token)
   end
 end
\ No newline at end of file
diff --git a/app/models/invitation.rb b/app/models/invitation.rb
index 619a09e..c6944d0 100644
--- a/app/models/invitation.rb
+++ b/app/models/invitation.rb
@@ -13,15 +13,45 @@ def generate_token
     end
   end
 
-  def accept
-    update!(accepted_at: Time.zone.now)
+  def decline_deadline
+    project_allocation.decline_deadline
   end
 
-  def reject
-    update!(rejected_at: Time.zone.now)
+  def expired?
+    Time.zone.now > decline_deadline
+  end
+
+  def accept!
+    return if expired?
+    update!(accepted_at: Time.zone.now, rejected_at: nil)
+    project_allocation.accept_funding!
+  end
+
+  def reject!
+    return if expired?
+    update!(rejected_at: Time.zone.now, accepted_at: nil)
     project_allocation.reject_funding!
   end
 
+  def accepted?
+    accepted_at.present?
+  end
+
+  def rejected?
+    rejected_at.present?
+  end
+
+  def send_email
+    MaintainerMailer.invitation_email(
+      project.contact_email,
+      project.to_s,
+      funder_names,
+      "$#{amount_cents / 100.0}",
+      "https://example.com/invite",
+      decline_deadline.strftime("%B %d, %Y")
+    ).deliver_now
+  end
+
   def html_url
     "https://staging.opencollective.com/#{ENV['OPENCOLLECTIVE_PARENT_SLUG']}/projects/#{project_allocation.fund.oc_project_slug}/expenses/#{member_invitation_id}"
   end
diff --git a/app/models/project_allocation.rb b/app/models/project_allocation.rb
index 3bfb11f..e5052c5 100644
--- a/app/models/project_allocation.rb
+++ b/app/models/project_allocation.rb
@@ -341,18 +341,16 @@ def decline_deadline
     created_at + 14.days
   end
 
-  def send_invitation_email
-    MaintainerMailer.invitation_email(
-      project.contact_email,
-      project.to_s,
-      funder_names,
-      "$#{amount_cents / 100.0}",
-      "https://example.com/invite",
-      decline_deadline.strftime("%B %d, %Y")
-    )
+  def send_invitation
+    # create invitation record
+    # send email
   end
 
   def reject_funding!
     project.update!(funding_rejected: true)
   end
+
+  def accept_funding!
+    project.update!(funding_rejected: false)
+  end
 end
diff --git a/app/views/invitations/show.html.erb b/app/views/invitations/show.html.erb
index 10b938a..13059d5 100644
--- a/app/views/invitations/show.html.erb
+++ b/app/views/invitations/show.html.erb
@@ -1,9 +1,17 @@
 <h1>Accept or reject the invitation!</h1>
 
-<p>Accept confirmation button</p>
+<% if @invitation.expired? %>
 
-<p>or they can update their funding.yml and we'll check it again</p>
+  <p>This invitation has expired</p>
 
-<p>also an option to reject</p>
+<% else %>
 
-<p>if it's been accepted/rejected already then show a message</p>
\ No newline at end of file
+  <p>Accept confirmation button</p>
+
+  <p>or they can update their funding.yml and we'll check it again</p>
+
+  <p>also an option to reject</p>
+
+  <p>if it's been accepted/rejected already then show a message</p>
+
+<% end %>
\ No newline at end of file