diff --git a/schema/mysql-changes/upgrade_22.sql b/schema/mysql-changes/upgrade_22.sql
new file mode 100644
index 00000000..418145c9
--- /dev/null
+++ b/schema/mysql-changes/upgrade_22.sql
@@ -0,0 +1,43 @@
+CREATE TABLE icinga_host_field (
+  host_id INT(10) UNSIGNED NOT NULL COMMENT 'Makes only sense for templates',
+  fieldname VARCHAR(64) NOT NULL,
+  caption VARCHAR(255) NOT NULL,
+  datatype_id INT(10) UNSIGNED NOT NULL,
+-- datatype_param? multiple ones?
+  default_value TEXT DEFAULT NULL,
+  format enum ('string', 'json', 'expression'),
+  PRIMARY KEY (host_id, fieldname),
+  KEY search_idx (fieldname),
+  CONSTRAINT icinga_host_field_host
+  FOREIGN KEY host(host_id)
+  REFERENCES icinga_host (id)
+    ON DELETE CASCADE
+    ON UPDATE CASCADE,
+  CONSTRAINT icinga_host_field_datatype
+  FOREIGN KEY datatype (datatype_id)
+  REFERENCES director_datatype (id)
+    ON DELETE RESTRICT
+    ON UPDATE CASCADE
+) ENGINE=InnoDB DEFAULT CHARSET=utf8;
+
+CREATE TABLE icinga_service_field (
+  service_id INT(10) UNSIGNED NOT NULL COMMENT 'Makes only sense for templates',
+  fieldname VARCHAR(64) NOT NULL,
+  caption VARCHAR(255) NOT NULL,
+  datatype_id INT(10) UNSIGNED NOT NULL,
+  -- datatype_param? multiple ones?
+  default_value TEXT DEFAULT NULL,
+  format enum ('string', 'json', 'expression'),
+  PRIMARY KEY (service_id, fieldname),
+  KEY search_idx (fieldname),
+  CONSTRAINT icinga_service_field_service
+    FOREIGN KEY service (service_id)
+    REFERENCES icinga_service (id)
+    ON DELETE CASCADE
+    ON UPDATE CASCADE,
+  CONSTRAINT icinga_service_field_datatype
+    FOREIGN KEY datatype (datatype_id)
+    REFERENCES director_datatype (id)
+    ON DELETE RESTRICT
+    ON UPDATE CASCADE
+) ENGINE=InnoDB DEFAULT CHARSET=utf8;
diff --git a/schema/mysql.sql b/schema/mysql.sql
index ad7569f7..24ed114d 100644
--- a/schema/mysql.sql
+++ b/schema/mysql.sql
@@ -116,7 +116,7 @@ CREATE TABLE director_datalist_entry (
 CREATE TABLE director_datatype (
   id INT(10) UNSIGNED AUTO_INCREMENT NOT NULL,
   datatype_name VARCHAR(255) NOT NULL,
-  -- ?? expression VARCHAR(255) NOT NULL,
+  datatype_class VARCHAR(255) NOT NULL,
   PRIMARY KEY (id),
   UNIQUE KEY datatype_name (datatype_name)
 ) ENGINE=InnoDB DEFAULT CHARSET=utf8;
@@ -387,6 +387,28 @@ CREATE TABLE icinga_host_inheritance (
     ON UPDATE CASCADE
 ) ENGINE=InnoDB DEFAULT CHARSET=utf8;
 
+CREATE TABLE icinga_host_field (
+  host_id INT(10) UNSIGNED NOT NULL COMMENT 'Makes only sense for templates',
+  fieldname VARCHAR(64) NOT NULL,
+  caption VARCHAR(255) NOT NULL,
+  datatype_id INT(10) UNSIGNED NOT NULL,
+-- datatype_param? multiple ones?
+  default_value TEXT DEFAULT NULL,
+  format enum ('string', 'json', 'expression'),
+  PRIMARY KEY (host_id, fieldname),
+  KEY search_idx (fieldname),
+  CONSTRAINT icinga_host_field_host
+  FOREIGN KEY host(host_id)
+  REFERENCES icinga_host (id)
+    ON DELETE CASCADE
+    ON UPDATE CASCADE,
+  CONSTRAINT icinga_host_field_datatype
+  FOREIGN KEY datatype (datatype_id)
+  REFERENCES director_datatype (id)
+    ON DELETE RESTRICT
+    ON UPDATE CASCADE
+) ENGINE=InnoDB DEFAULT CHARSET=utf8;
+
 CREATE TABLE icinga_host_var (
   host_id INT(10) UNSIGNED NOT NULL,
   varname VARCHAR(255) DEFAULT NULL,
@@ -488,6 +510,28 @@ CREATE TABLE icinga_service_var (
     ON UPDATE CASCADE
 ) ENGINE=InnoDB DEFAULT CHARSET=utf8;
 
+CREATE TABLE icinga_service_field (
+  service_id INT(10) UNSIGNED NOT NULL COMMENT 'Makes only sense for templates',
+  fieldname VARCHAR(64) NOT NULL,
+  caption VARCHAR(255) NOT NULL,
+  datatype_id INT(10) UNSIGNED NOT NULL,
+  -- datatype_param? multiple ones?
+  default_value TEXT DEFAULT NULL,
+  format enum ('string', 'json', 'expression'),
+  PRIMARY KEY (service_id, fieldname),
+  KEY search_idx (fieldname),
+  CONSTRAINT icinga_service_field_service
+    FOREIGN KEY service (service_id)
+    REFERENCES icinga_service (id)
+    ON DELETE CASCADE
+    ON UPDATE CASCADE,
+  CONSTRAINT icinga_service_field_datatype
+    FOREIGN KEY datatype (datatype_id)
+    REFERENCES director_datatype (id)
+    ON DELETE RESTRICT
+    ON UPDATE CASCADE
+) ENGINE=InnoDB DEFAULT CHARSET=utf8;
+
 CREATE TABLE icinga_host_service (
     host_id INT(10) UNSIGNED NOT NULL,
   service_id INT(10) UNSIGNED NOT NULL,
diff --git a/schema/pgsql-changes/upgrade_22.sql b/schema/pgsql-changes/upgrade_22.sql
new file mode 100644
index 00000000..6106f145
--- /dev/null
+++ b/schema/pgsql-changes/upgrade_22.sql
@@ -0,0 +1,52 @@
+CREATE TABLE icinga_host_field (
+  host_id integer NOT NULL,
+  fieldname character varying(64) NOT NULL,
+  caption character varying(255) NOT NULL,
+  datatype_id integer NOT NULL,
+-- datatype_param? multiple ones?
+  default_value text DEFAULT NULL,
+  format enum_property_format,
+  PRIMARY KEY (host_id, fieldname),
+  CONSTRAINT icinga_host_field_host
+  FOREIGN KEY (host_id)
+  REFERENCES icinga_host (id)
+    ON DELETE CASCADE
+    ON UPDATE CASCADE,
+  CONSTRAINT icinga_host_field_datatype
+  FOREIGN KEY datatype (datatype_id)
+  REFERENCES director_datatype (id)
+    ON DELETE RESTRICT
+    ON UPDATE CASCADE
+);
+
+CREATE UNIQUE INDEX host_field_key ON icinga_host_field (host_id, fieldname);
+CREATE INDEX host_field_search_idx ON icinga_host_field (fieldname);
+CREATE INDEX host_field_host ON icinga_host_field (host_id);
+COMMENT ON COLUMN icinga_host_field.host_id IS 'Makes only sense for templates';
+
+
+CREATE TABLE icinga_service_field (
+  service_id integer NOT NULL,
+  fieldname character varying(64) NOT NULL,
+  caption character varying(255) NOT NULL,
+  datatype_id integer NOT NULL,
+-- datatype_param? multiple ones?
+  default_value text DEFAULT NULL,
+  format enum_property_format,
+  PRIMARY KEY (service_id, fieldname),
+  CONSTRAINT icinga_service_field_service
+  FOREIGN KEY (service_id)
+  REFERENCES icinga_service (id)
+    ON DELETE CASCADE
+    ON UPDATE CASCADE,
+  CONSTRAINT icinga_service_field_datatype
+  FOREIGN KEY datatype (datatype_id)
+  REFERENCES director_datatype (id)
+    ON DELETE RESTRICT
+    ON UPDATE CASCADE
+);
+
+CREATE UNIQUE INDEX service_field_key ON icinga_service_field (service_id, fieldname);
+CREATE INDEX service_field_search_idx ON icinga_service_field (fieldname);
+CREATE INDEX service_field_service ON icinga_service_field (service_id);
+COMMENT ON COLUMN icinga_service_field.service_id IS 'Makes only sense for templates';
diff --git a/schema/pgsql.sql b/schema/pgsql.sql
index 6ba9ad16..a442e9a2 100644
--- a/schema/pgsql.sql
+++ b/schema/pgsql.sql
@@ -482,6 +482,33 @@ CREATE INDEX host_inheritance_host ON icinga_host_inheritance (host_id);
 CREATE INDEX host_inheritance_host_parent ON icinga_host_inheritance (parent_host_id);
 
 
+CREATE TABLE icinga_host_field (
+  host_id integer NOT NULL,
+  fieldname character varying(64) NOT NULL,
+  caption character varying(255) NOT NULL,
+  datatype_id integer NOT NULL,
+-- datatype_param? multiple ones?
+  default_value text DEFAULT NULL,
+  format enum_property_format,
+  PRIMARY KEY (host_id, fieldname),
+  CONSTRAINT icinga_host_field_host
+  FOREIGN KEY (host_id)
+  REFERENCES icinga_host (id)
+    ON DELETE CASCADE
+    ON UPDATE CASCADE,
+  CONSTRAINT icinga_host_field_datatype
+  FOREIGN KEY datatype (datatype_id)
+  REFERENCES director_datatype (id)
+    ON DELETE RESTRICT
+    ON UPDATE CASCADE
+);
+
+CREATE UNIQUE INDEX host_field_key ON icinga_host_field (host_id, fieldname);
+CREATE INDEX host_field_search_idx ON icinga_host_field (fieldname);
+CREATE INDEX host_field_host ON icinga_host_field (host_id);
+COMMENT ON COLUMN icinga_host_field.host_id IS 'Makes only sense for templates';
+
+
 CREATE TABLE icinga_host_var (
   host_id integer NOT NULL,
   varname character varying(255) DEFAULT NULL,
@@ -583,6 +610,33 @@ CREATE INDEX service_inheritance_service ON icinga_service_inheritance (service_
 CREATE INDEX service_inheritance_service_parent ON icinga_service_inheritance (parent_service_id);
 
 
+CREATE TABLE icinga_service_field (
+  service_id integer NOT NULL,
+  fieldname character varying(64) NOT NULL,
+  caption character varying(255) NOT NULL,
+  datatype_id integer NOT NULL,
+-- datatype_param? multiple ones?
+  default_value text DEFAULT NULL,
+  format enum_property_format,
+  PRIMARY KEY (service_id, fieldname),
+  CONSTRAINT icinga_service_field_service
+  FOREIGN KEY (service_id)
+  REFERENCES icinga_service (id)
+    ON DELETE CASCADE
+    ON UPDATE CASCADE,
+  CONSTRAINT icinga_service_field_datatype
+  FOREIGN KEY datatype (datatype_id)
+  REFERENCES director_datatype (id)
+    ON DELETE RESTRICT
+    ON UPDATE CASCADE
+);
+
+CREATE UNIQUE INDEX service_field_key ON icinga_service_field (service_id, fieldname);
+CREATE INDEX service_field_search_idx ON icinga_service_field (fieldname);
+CREATE INDEX service_field_service ON icinga_service_field (service_id);
+COMMENT ON COLUMN icinga_service_field.service_id IS 'Makes only sense for templates';
+
+
 CREATE TABLE icinga_service_var (
   service_id integer NOT NULL,
   varname character varying(255) DEFAULT NULL,