diff --git a/composer/schema/README.txt b/composer/schema/README.txt
index 348db3d..3943641 100644
--- a/composer/schema/README.txt
+++ b/composer/schema/README.txt
@@ -24,17 +24,20 @@ objects.
   ...     pass
 
 The schema will be connected with an object via an instance adapter.
+In addition, we need a field instance adapter that cares for  the
+correct conversion of input data to context attributes.
 
   >>> from cybertools.composer.schema.instance import Editor
+  >>> from cybertools.composer.schema.field import FieldInstance
   >>> from zope import component
   >>> component.provideAdapter(Editor, (Service,), name="service.edit")
+  >>> component.provideAdapter(FieldInstance)
 
   >>> srv = Service()
   >>> inst = component.getAdapter(srv, name='service.edit')
   >>> inst.template = serviceSchema
-  >>> inst.applyTemplate()
-  title -
-  description -
-  start -
-  end -
-  capacity -
+  >>> inst.applyTemplate(data=dict(title='Service', capacity='30'))
+  <...FormState object ...>
+
+  >>> srv.title, srv.description, srv.capacity
+  (u'Service', u'', u'30')
diff --git a/composer/schema/browser/schema_macros.pt b/composer/schema/browser/schema_macros.pt
index a3d8b4f..c50d19f 100755
--- a/composer/schema/browser/schema_macros.pt
+++ b/composer/schema/browser/schema_macros.pt
@@ -7,12 +7,11 @@
   <tal:define define="manageMode manageMode|view/manageMode|nothing;
                       fields view/fields;
                       data view/data">
-    <table class="listing" style="width: auto">
+    <table style="width: 100%">
       <tal:fields repeat="field fields">
         <tal:field define="name field/name;
-                           typeInfo field/getFieldTypeInfo;
                            errors state/fieldInstances/?name/errors|python: [];">
-          <metal:field use-macro="python: view.schemaMacros[typeInfo.fieldMacro]" />
+          <metal:field use-macro="python: view.schemaMacros[field.fieldRenderer]" />
         </tal:field>
       </tal:fields>
     </table>
@@ -43,7 +42,7 @@
             </td>
             <td class="field" style="border-top: none">
               <metal:input use-macro="python:
-                    view.schemaMacros[typeInfo.inputMacro]" />
+                    view.schemaMacros[field.inputRenderer]" />
             </td>
           </tal:field>
         </tr>
@@ -61,36 +60,45 @@
 
 
 <metal:textline define-macro="input_textline">
-    <input type="text" name="field" style="width: 300px"
-           tal:define="width field/width|python:300"
+    <input type="text" name="field" style="width: 450px"
+           tal:define="width field/width|nothing"
            tal:attributes="name name;
-                           style python: 'width: %ipx' % (width or 300);
-                           value data/?name|field/defaultValue|string:" />
+                           style python:
+                                'width: %s' % (width and str(width)+'px' or '450px');
+                           value data/?name" />
 </metal:textline>
 
 
 <metal:textarea define-macro="input_textarea">
-    <textarea name="field" rows="3" style="width: 300px"
-           tal:define="width field/width|python:300;
+    <textarea name="field" rows="3" style="width: 450px"
+           tal:define="width field/width|nothing;
                        height field/height|python:3"
            tal:attributes="name name;
                            rows python: height or 3;
-                           style python: 'width: %ipx' % (width or 300)"
-           tal:content="data/?name|field/defaultValue|string:">
+                           style python:
+                                'width: %s' % (width and str(width)+'px' or '450px');"
+           tal:content="data/?name">
     </textarea>
 </metal:textarea>
 
 
+<metal:upload define-macro="input_fileupload">
+    <input type="file" name="field"
+           tal:attributes="name name;" />
+</metal:upload>
+
+
 <metal:dropdown define-macro="input_dropdown">
-    <select name="field" style="width: 100px"
-           tal:define="width field/width|python:100"
+    <select name="field" style="width: auto"
+           tal:define="width field/width|nothing"
            tal:attributes="name name;
-                           style python: 'width: %ipx' % (width or 100);">
+                           style python:
+                                'width: %s' % (width and str(width)+'px' or '');">
       <option tal:repeat="item field/getVocabularyItems"
               tal:content="item/title"
               tal:attributes="value item/token;
                               selected python:
-                    item['token'] == data.get(name, field.defaultValue)">Mrs</option>
+                    item['token'] == data[name]">Mrs</option>
     </select>
 </metal:dropdown>
 
diff --git a/composer/schema/field.py b/composer/schema/field.py
index 2e18d31..b661c5d 100644
--- a/composer/schema/field.py
+++ b/composer/schema/field.py
@@ -40,8 +40,8 @@ class Field(Component):
     required = False
     standardFieldName = None
     vocabulary = None
-    defaultValue = None
     renderFactory = None
+    default = None
 
     def __init__(self, name, title=None, fieldType='textline', **kw):
         assert name
@@ -57,6 +57,24 @@ class Field(Component):
     def name(self):
         return self.__name__
 
+    @property
+    def defaultValue(self):
+        if callable(self.default):
+            return self.default()
+        return self.default
+
+    @property
+    def fieldRenderer(self):
+        return self.getFieldTypeInfo().fieldRenderer
+
+    @property
+    def inputRenderer(self):
+        return self.getFieldTypeInfo().inputRenderer
+
+    @property
+    def storeData(self):
+        return self.getFieldTypeInfo().storeData
+
     def getTitleValue(self):
         return self.title or self.name
 
@@ -66,7 +84,7 @@ class Field(Component):
             voc = voc.splitlines()
             return [dict(token=t, title=t) for t in voc if t.strip()]
         else:
-            return [dict(token=t.token, title=t.title) for t in voc]
+            return [dict(token=t.token, title=t.title or t.value) for t in voc]
 
     def getFieldTypeInfo(self):
         return fieldTypes.getTerm(self.fieldType)
@@ -135,3 +153,12 @@ class NumberFieldInstance(FieldInstance):
                 int(value)
             except (TypeError, ValueError):
                 self.setError('invalid_number')
+
+
+class FileUploadFieldInstance(FieldInstance):
+
+    def marshall(self, value):
+        return value
+
+    def unmarshall(self, value):
+        return value
diff --git a/composer/schema/instance.py b/composer/schema/instance.py
index 747e87d..0156d39 100644
--- a/composer/schema/instance.py
+++ b/composer/schema/instance.py
@@ -47,14 +47,13 @@ class Instance(BaseInstance):
         template = self.template
         if template is not None:
             for f in template.components:
-                fieldType = f.getFieldTypeInfo()
-                if not fieldType.storeData:
+                if not f.storeData:
                     # a dummy field, e.g. a spacer
                     continue
                 fi = f.getFieldInstance()
                 name = f.name
-                #value = getattr(self.context, name, field.default)
-                value = getattr(self.context, name, u'')
+                value = getattr(self.context, name, f.defaultValue)
+                #value = getattr(self.context, name, u'')
                 value = (mode == 'view' and fi.display(value)) or fi.marshall(value)
                 result[name] = value
         return result
@@ -69,12 +68,44 @@ class Editor(BaseInstance):
     template = None
 
     def applyTemplate(self, data={}, *args, **kw):
-        for c in self.template.components:
-            # TODO: implement the real stuff
-            # save data (if available) in context
-            # build sequence of fields with data from context
-            # or directly use request...
-            print c.name, getattr(self.context, c.name, '-')
+        fieldHandlers = kw.get('fieldHandlers', {})
+        template = self.template
+        context = self.context
+        formState = self.validate(data)
+        if template is None:
+            return formState
+        if formState.severity > 0:
+            # don't do anything if there is an error
+            return formState
+        for f in template.components:
+            if not f.storeData:
+                # a dummy field, e.g. a spacer
+                continue
+            name = f.name
+            ftype = f.fieldType
+            fi = formState.fieldInstances[name]
+            value = fi.unmarshall(data.get(name, u''))
+            if ftype in fieldHandlers:  # caller wants special treatment of field
+                fieldHandlers[ftype](context, value, fi, formState)
+            else:
+                oldValue = getattr(context, name, None)
+                if value != oldValue:
+                    setattr(context, name, value)
+                    fi.change = (oldValue, value)
+                    formState.changed = True
+        return formState
+
+    def validate(self, data):
+        formState = FormState()
+        if self.template is None:
+            return formState
+        for f in self.template.fields:
+            fi = f.getFieldInstance()
+            value = data.get(f.name)
+            fi.validate(value)
+            formState.fieldInstances.append(fi)
+            formState.severity = max(formState.severity, fi.severity)
+        return formState
 
 
 class ClientInstance(object):
@@ -111,8 +142,7 @@ class ClientInstance(object):
         if template is not None:
             values = attrs.get(self.aspect, {})
             for f in template.fields:
-                fieldType = f.getFieldTypeInfo()
-                if not fieldType.storeData:
+                if not f.storeData:
                     # a dummy field, e.g. a spacer
                     continue
                 fi = f.getFieldInstance()
@@ -147,13 +177,12 @@ class ClientInstanceEditor(ClientInstance):
         values = attrs.setdefault(self.aspect, OOBTree())
         for f in template.fields:
             name = f.name
-            fieldType = f.getFieldTypeInfo()
-            if not fieldType.storeData:
+            if not f.storeData:
                 # a dummy field, e.g. a spacer
                 continue
-            fi = formState.fieldInstances[name]
-            value = fi.unmarshall(data.get(name))
             if name in data:
+                fi = formState.fieldInstances[name]
+                value = fi.unmarshall(data.get(name))
                 oldValue = values.get(name)
                 if value != oldValue:
                     values[name] = value
diff --git a/composer/schema/interfaces.py b/composer/schema/interfaces.py
index 299e086..143e6f5 100644
--- a/composer/schema/interfaces.py
+++ b/composer/schema/interfaces.py
@@ -63,8 +63,8 @@ class FieldType(SimpleTerm):
     def __init__(self, value, token=None, title=None, **kw):
         super(FieldType, self).__init__(value, token, title)
         self.name = value
-        self.fieldMacro = 'field'
-        self.inputMacro = 'input_' + self.name
+        self.fieldRenderer = 'field'
+        self.inputRenderer = 'input_' + self.name
         self.storeData = True
         self.instanceName = ''
         for k, v in kw.items():
@@ -74,13 +74,15 @@ class FieldType(SimpleTerm):
 fieldTypes = SimpleVocabulary((
     FieldType('textline', 'textline', u'Textline'),
     FieldType('textarea', 'textarea', u'Textarea'),
-    FieldType('number', 'number', u'Number', inputMacro='input_textline',
-              instanceName='number'),
+    FieldType('number', 'number', u'Number',
+              inputRenderer='input_textline', instanceName='number'),
     #FieldType('date', 'date', u'Date'),
+    FieldType('fileupload', 'fileupload', u'File upload',
+              instanceName='fileupload'),
     #FieldType('checkbox', 'checkbox', u'Checkbox'),
     FieldType('dropdown', 'dropdown', u'Drop-down selection'),
-    FieldType('spacer', 'spacer', u'Spacer', fieldMacro='field_spacer',
-              storeData=False),
+    FieldType('spacer', 'spacer', u'Spacer',
+              fieldRenderer='field_spacer', storeData=False),
 ))
 
 standardFieldNames = SimpleVocabulary((
@@ -146,6 +148,17 @@ class IField(IComponent):
                         '(only for dropdown and other selection fields)'),
                 required=False,)
 
+    fieldRenderer = Attribute('Name of a renderer (i.e. a ZPT macro or '
+                        'an adapter) that is responsible for rendering '
+                        '(presenting) the field as a whole.')
+    inputRenderer = Attribute('Name of a renderer (i.e. a ZPT macro or '
+                        'an adapter) that is responsible for rendering '
+                        '(presenting) the part of the field that allows '
+                        'data input.')
+    storeData = Attribute('Boolean value, true when this field provides '
+                        'data that may be stored in a context object, '
+                        'false for dummy fields like spacers.')
+
     renderFactory = Attribute('A class or another factory providing an '
                         'object used for rendering the data e.g. as a '
                         'cell on a tabular report. See cybertools.reporter. '
diff --git a/composer/schema/util.py b/composer/schema/util.py
index 5c38c8e..a81e4e9 100644
--- a/composer/schema/util.py
+++ b/composer/schema/util.py
@@ -47,10 +47,10 @@ def getSchemaFromInterface(ifc, manager):
             info = fieldMapping[field.__class__]
             voc = getattr(field, 'vocabulary', ()) or getattr(field, 'vocabularyName', None)
             f = Field(field.getName(),
-                    fieldType = info[0],
+                    fieldType=info[0],
                     required=field.required,
                     default=field.default,
-                    default_method=getattr(field, 'default_method', None),
+                    #default_method=getattr(field, 'default_method', None),
                     vocabulary=voc,
                     title=field.title,
                     description=field.description)