diff --git a/src/main/asciidoc/developer_documentation.adoc b/src/main/asciidoc/developer_documentation.adoc
index 3e2dd9d..0004f6a 100644
--- a/src/main/asciidoc/developer_documentation.adoc
+++ b/src/main/asciidoc/developer_documentation.adoc
@@ -347,3 +347,6 @@ image:models/design/seq_inventory.svg[sequence diagram - inventory]
 === Order
 image:models/design/seq_order.svg[sequence diagram - order]
 
+=== OrderCatalog
+image:models/design/seq_orderCatalog.svg[sequence diagram - orderCatalog]
+
diff --git a/src/main/asciidoc/models/design/seq_orderCatalog.puml b/src/main/asciidoc/models/design/seq_orderCatalog.puml
new file mode 100644
index 0000000..7ac65dc
--- /dev/null
+++ b/src/main/asciidoc/models/design/seq_orderCatalog.puml
@@ -0,0 +1,62 @@
+' SPDX-License-Identifier: AGPL-3.0-or-later
+' SPDX-FileCopyrightText: 2023-2024 swt23w23
+@startuml
+participant Customer
+participant Administrator
+participant CatalogController
+participant CustomCatalogEntryRepository
+participant CartService
+participant Spring
+
+== Add catalog entry to cart ==
+
+activate Customer
+Customer -> CatalogController : catalog(model : Model)
+activate CatalogController
+CatalogController -> CustomCatalogEntryRepository : findAll()
+activate CustomCatalogEntryRepository
+CustomCatalogEntryRepository --> CatalogController : Streamable<CustomCatalogEntry>
+deactivate CustomCatalogEntryRepository
+CatalogController -> Spring : model.addAttribute()
+activate Spring
+Spring --> CatalogController : Model
+deactivate Spring
+CatalogController --> Customer : "catalog.html"
+deactivate CatalogController
+
+Customer -> CatalogController : addToCart(catalogEntryID : long)
+activate CatalogController
+CatalogController -> CustomCatalogEntryRepository : findById(catalogEntryID)
+activate CustomCatalogEntryRepository
+CustomCatalogEntryRepository --> CatalogController : CustomCatalogEntry
+deactivate CustomCatalogEntryRepository
+CatalogController -> CartService : getCart()
+activate CartService
+CartService --> CatalogController : cart : CustomCart
+deactivate CartService
+CatalogController -> CatalogController : cart.addOrUpdateItem()
+CatalogController -> CatalogController : cart.setOrderType()
+CatalogController -> CartService : setCart()
+activate CartService
+CartService --> CatalogController
+deactivate CartService
+CatalogController --> Customer : "redirect:/event"
+deactivate CatalogController
+deactivate Customer
+
+== Access order catalog editor ==
+
+Administrator -> CatalogController : editCatalog(model : Model)
+activate Administrator
+activate CatalogController
+CatalogController -> Spring : model.addAttribute()
+activate Spring
+Spring --> CatalogController : Model
+deactivate Spring
+CatalogController -> Inventory : findAll()
+activate Inventory
+Inventory --> CatalogController : List<Product>
+deactivate Inventory
+CatalogController --> Administrator : "catalog_editor"
+
+@enduml
diff --git a/src/main/asciidoc/models/design/seq_orderCatalog.svg b/src/main/asciidoc/models/design/seq_orderCatalog.svg
new file mode 100644
index 0000000..d9e5e0d
--- /dev/null
+++ b/src/main/asciidoc/models/design/seq_orderCatalog.svg
@@ -0,0 +1,3 @@
+version https://git-lfs.github.com/spec/v1
+oid sha256:015f734908c403a86d8463386d8434f79773e6e08446ed9f569be37f3fed5ab0
+size 18243