diff --git a/nummi/main/models.py b/nummi/main/models.py
index 073fafd..5b3773a 100644
--- a/nummi/main/models.py
+++ b/nummi/main/models.py
@@ -12,7 +12,7 @@ class Category(models.Model):
     parent = models.ForeignKey("self", on_delete=models.SET_NULL, blank=True, null=True)
 
     def __str__(self):
-        if self.parent is None:
+        if self.parent is None or self.parent == self:
             return self.name
         return f"{self.parent}>{self.name}"
 
@@ -24,7 +24,7 @@ class Category(models.Model):
 
     @property
     def tree(self):
-        if self.parent is None:
+        if self.parent is None or self.parent == self:
             return [self.name]
         return self.parent.tree + [self.name]
 
@@ -32,6 +32,12 @@ class Category(models.Model):
         ordering = ["full_name"]
 
 
+class CategoryForm(ModelForm):
+    class Meta:
+        model = Category
+        fields = ["name", "parent"]
+
+
 class Transaction(models.Model):
     id = models.UUIDField(primary_key=True, default=uuid.uuid4, editable=False)
     name = models.CharField(max_length=256, default="Transaction")
@@ -49,6 +55,9 @@ class Transaction(models.Model):
             return f"{res} ({self.category})"
         return res
 
+    class Meta:
+        ordering = ["-date"]
+
 
 class TransactionForm(ModelForm):
     class Meta:
diff --git a/nummi/main/static/css/index.css b/nummi/main/static/css/index.css
index c4c798f..90649d9 100644
--- a/nummi/main/static/css/index.css
+++ b/nummi/main/static/css/index.css
@@ -42,7 +42,6 @@
 ul#categories {
 	list-style-type: "– ";
 }
-#categories ul {
-	list-style-type: "↳ ";
-	padding-left: 1.5em;
-}
+ul#categories li.cat2 {margin-left: 1em}
+ul#categories li.cat3 {margin-left: 2em}
+ul#categories li.cat4 {margin-left: 3em}
diff --git a/nummi/main/templates/main/category.html b/nummi/main/templates/main/category.html
new file mode 100644
index 0000000..07ed357
--- /dev/null
+++ b/nummi/main/templates/main/category.html
@@ -0,0 +1,20 @@
+{% extends "main/base.html" %}
+
+{% block body %}
+<a href="{% url 'index' %}">Home</a>
+
+<h1>{{ category.tree|join:" → " }}</h1>
+
+<form action="{% url 'update_category' category.id %}" method="post">
+	{% csrf_token %}
+	{{ form.as_p }}
+	<input type="submit" />
+</form>
+
+{% if transactions %}
+<h2>Transactions ({{ transactions|length }})</h2>
+<ul>
+	{{ transactions|unordered_list }}
+</ul>
+{% endif %}
+{% endblock %}
diff --git a/nummi/main/templates/main/index.html b/nummi/main/templates/main/index.html
index 4a394a4..262b396 100644
--- a/nummi/main/templates/main/index.html
+++ b/nummi/main/templates/main/index.html
@@ -37,7 +37,13 @@
 
 {% if categories %}
 	<ul id="categories">
-		{{ categories|unordered_list }}
+		{% for cat in categories %}
+		<li class="{% if cat.tree|length > 3 %}cat4{% else %}cat{{ cat.tree|length }}{% endif %}">
+			<a href="{% url 'category' cat.id %}">
+				{% if cat.tree|length > 3 %}{{ cat.tree|slice:"3:"|join:" → " }}{% else %}{{ cat.name }}{% endif %}
+			</a>
+		</li>
+		{% endfor %}
 	</ul>
 {% endif %}
 
diff --git a/nummi/main/urls.py b/nummi/main/urls.py
index 194ddb6..4114aaf 100644
--- a/nummi/main/urls.py
+++ b/nummi/main/urls.py
@@ -18,4 +18,7 @@ urlpatterns = [
         name="del_invoice",
     ),
     path("invoice/<uuid>", views.invoice, name="invoice"),
+    path("category", views.category, name="category"),
+    path("category/<uuid>", views.category, name="category"),
+    path("category/<uuid>/update", views.update_category, name="update_category"),
 ]
diff --git a/nummi/main/views.py b/nummi/main/views.py
index 95bef5e..8afcc8c 100644
--- a/nummi/main/views.py
+++ b/nummi/main/views.py
@@ -3,29 +3,24 @@ from django.http import HttpResponse
 from django.contrib.auth.decorators import login_required
 from django.contrib.auth import views as auth_views
 
-from .models import Transaction, TransactionForm, Invoice, InvoiceForm, Category
+from .models import (
+    Transaction,
+    TransactionForm,
+    Invoice,
+    InvoiceForm,
+    Category,
+    CategoryForm,
+)
 
 
 @login_required
 def index(request):
     _transactions = Transaction.objects.order_by("-date")[:5]
-    _categories = Category.objects.filter(parent=None)
-
-    def _cat_list(cat):
-        children = []
-        for child in Category.objects.filter(parent=cat):
-            children += _cat_list(child)
-        if len(children) == 0:
-            return (cat.name,)
-        return cat.name, children
-
-    _cats = []
-    for cat in _categories:
-        _cats += _cat_list(cat)
+    _categories = Category.objects.all()
 
     context = {
         "transactions": _transactions,
-        "categories": _cats,
+        "categories": _categories,
     }
     return render(request, "main/index.html", context)
 
@@ -91,3 +86,33 @@ def del_invoice(request, uuid, invoice_id):
     _invoice = get_object_or_404(Invoice, id=invoice_id)
     _invoice.delete()
     return redirect(transaction, uuid=uuid)
+
+
+@login_required
+def category(request, uuid=None):
+    if uuid is None:
+        _category = Category()
+        _transactions = None
+    else:
+        _category = get_object_or_404(Category, id=uuid)
+        _transactions = Transaction.objects.filter(category=_category)
+    return render(
+        request,
+        "main/category.html",
+        {
+            "category": _category,
+            "form": CategoryForm(instance=_category),
+            "transactions": _transactions,
+        },
+    )
+
+
+@login_required
+def update_category(request, uuid):
+    try:
+        _category = Category.objects.get(id=uuid)
+    except Category.DoesNotExist:
+        _category = Category(id=uuid)
+    _form = CategoryForm(request.POST, instance=_category)
+    _form.save()
+    return redirect(category, uuid=uuid)