diff --git a/CHANGELOG b/CHANGELOG
index 7776d3fdc0..6f17754af8 100644
--- a/CHANGELOG
+++ b/CHANGELOG
@@ -1,3 +1,4 @@
+* Add PYSON widget
 * Allow to define the text color and background color in calendar view
 * Allow to override cache implementation
 * Add button rule
diff --git a/trytond/ir/ui/form.rnc b/trytond/ir/ui/form.rnc
index faa67d9656..148262ab3d 100644
--- a/trytond/ir/ui/form.rnc
+++ b/trytond/ir/ui/form.rnc
@@ -65,6 +65,7 @@ attlist.field &=
     | "richtext"
     | "dict"
     | "multiselection"
+    | "pyson"
   }?
 attlist.field &= attribute fill { "0" | "1" }?
 attlist.field &= attribute yexpand { "0" | "1" }?
diff --git a/trytond/ir/ui/form.rng b/trytond/ir/ui/form.rng
index db3fa353b9..d7c1fd6aae 100644
--- a/trytond/ir/ui/form.rng
+++ b/trytond/ir/ui/form.rng
@@ -161,6 +161,7 @@
           <value>richtext</value>
           <value>dict</value>
           <value>multiselection</value>
+          <value>pyson</value>
         </choice>
       </attribute>
     </optional>
diff --git a/trytond/ir/view/action_act_window_domain_form.xml b/trytond/ir/view/action_act_window_domain_form.xml
index d3adf22ad0..0d0370b8a3 100644
--- a/trytond/ir/view/action_act_window_domain_form.xml
+++ b/trytond/ir/view/action_act_window_domain_form.xml
@@ -14,5 +14,5 @@ this repository contains the full copyright notices and license terms. -->
     <field name="act_window"/>
     <newline/>
     <label name="domain"/>
-    <field name="domain" colspan="5"/>
+    <field name="domain" colspan="5" widget="pyson"/>
 </form>
diff --git a/trytond/ir/view/action_act_window_form.xml b/trytond/ir/view/action_act_window_form.xml
index 879ce4b851..4c9947ccf5 100644
--- a/trytond/ir/view/action_act_window_form.xml
+++ b/trytond/ir/view/action_act_window_form.xml
@@ -21,13 +21,13 @@ this repository contains the full copyright notices and license terms. -->
             <field name="act_window_domains" colspan="4"
                 view_ids="ir.act_window_domain_view_list2"/>
             <label name="domain"/>
-            <field name="domain" colspan="3"/>
+            <field name="domain" colspan="3" widget="pyson"/>
             <label name="context"/>
-            <field name="context" colspan="3"/>
+            <field name="context" colspan="3" widget="pyson"/>
             <label name="order"/>
             <field name="order" colspan="3"/>
             <label name="search_value"/>
-            <field name="search_value" colspan="3"/>
+            <field name="search_value" colspan="3" widget="pyson"/>
             <label name="limit"/>
             <field name="limit"/>
         </page>
diff --git a/trytond/ir/view/rule_form.xml b/trytond/ir/view/rule_form.xml
index f9bb68772b..e931ec2ff5 100644
--- a/trytond/ir/view/rule_form.xml
+++ b/trytond/ir/view/rule_form.xml
@@ -6,5 +6,5 @@ this repository contains the full copyright notices and license terms. -->
     <field name="rule_group"/>
     <newline/>
     <label name="domain"/>
-    <field name="domain" colspan="3"/>
+    <field name="domain" colspan="3" widget="pyson"/>
 </form>
diff --git a/trytond/ir/view/trigger_form.xml b/trytond/ir/view/trigger_form.xml
index e7b510161d..419c0b7c1c 100644
--- a/trytond/ir/view/trigger_form.xml
+++ b/trytond/ir/view/trigger_form.xml
@@ -19,7 +19,7 @@ this repository contains the full copyright notices and license terms. -->
         <field name="on_delete" xexpand="0"/>
     </group>
     <label name="condition"/>
-    <field name="condition" colspan="3"/>
+    <field name="condition" colspan="3" widget="pyson"/>
     <label name="limit_number"/>
     <field name="limit_number"/>
     <label name="minimum_time_delay"/>
diff --git a/trytond/ir/view/ui_view_form.xml b/trytond/ir/view/ui_view_form.xml
index fdc7498494..b6e932a5d8 100644
--- a/trytond/ir/view/ui_view_form.xml
+++ b/trytond/ir/view/ui_view_form.xml
@@ -9,7 +9,7 @@ this repository contains the full copyright notices and license terms. -->
     <label name="inherit"/>
     <field name="inherit"/>
     <label name="domain"/>
-    <field name="domain"/>
+    <field name="domain" widget="pyson"/>
     <label name="priority"/>
     <field name="priority"/>
     <label name="field_childs"/>