diff --git a/yopa-web/resources/templates/relation_create.html.tera b/yopa-web/resources/templates/relation_create.html.tera
new file mode 100644
index 0000000..f1e2c90
--- /dev/null
+++ b/yopa-web/resources/templates/relation_create.html.tera
@@ -0,0 +1,39 @@
+{% extends "_layout" %}
+
+{% block title -%}
+Define relation
+{%- endblock %}
+
+{% block nav -%}
+<a href="/">Home</a>
+{%- endblock %}
+
+{% block content -%}
+
+<h1>Define new relation from "{{object.name}}"</h1>
+
+<form action="/model/relation/create" method="POST">
+	<input type="hidden" name="object" value="{{object.id}}">
+
+	<label for="name">Name:</label>
+	<input type="text" id="name" name="name"><br>
+
+	<label for="optional">Optional:</label>
+	<input type="checkbox" name="optional" id="optional" value="1">
+	<br>
+
+	<label for="multiple">Multiple:</label>
+	<input type="checkbox" name="multiple" id="multiple" value="1"><br>
+
+	<label for="related">Related object:</label>
+	<select name="related" id="related">
+		{% for m in models %}
+		<option value="{{ m.id }}">{{ m.name }}</option>
+		{% endfor %}
+	</select><br>
+
+	<input type="submit" value="Save">
+</form>
+
+
+{%- endblock %}
diff --git a/yopa-web/src/main.rs b/yopa-web/src/main.rs
index 5f6f373..443e972 100644
--- a/yopa-web/src/main.rs
+++ b/yopa-web/src/main.rs
@@ -97,6 +97,8 @@ async fn main() -> std::io::Result<()> {
             .service(routes::index)
             .service(routes::object_model_create_form)
             .service(routes::object_model_create)
+            .service(routes::relation_model_create_form)
+            .service(routes::relation_model_create)
             .service(routes::object_model_delete)
             .service(routes::relation_model_delete)
             .service(routes::property_model_delete)
@@ -107,6 +109,7 @@ async fn main() -> std::io::Result<()> {
         .run().await
 }
 
+
 fn init_yopa() -> YopaStoreWrapper {
     let mut store = Storage::new();
 
diff --git a/yopa-web/src/routes.rs b/yopa-web/src/routes.rs
index c26630f..f5b54f6 100644
--- a/yopa-web/src/routes.rs
+++ b/yopa-web/src/routes.rs
@@ -1,12 +1,15 @@
 use actix_web::{web, HttpRequest, Responder, HttpResponse};
 use crate::TERA;
 use crate::tera_ext::TeraExt;
-use yopa::{Storage, StorageError};
+use yopa::{Storage, StorageError, ID};
 use serde::{Deserialize, Serialize};
 use yopa::model::{PropertyModel, RelationModel, ObjectModel};
 use std::ops::DerefMut;
 use actix_session::Session;
 use crate::session_ext::SessionExt;
+use std::str::FromStr;
+use std::fmt::{Debug, Display};
+use actix_web::http::header::IntoHeaderValue;
 
 #[derive(Serialize, Debug)]
 struct ObjectModelDisplay<'a> {
@@ -23,12 +26,39 @@ struct RelationModelDisplay<'a> {
     properties: Vec<&'a PropertyModel>,
 }
 
-fn redirect(path : impl AsRef<str>) -> actix_web::Result<impl Responder> {
+fn redirect(path : impl IntoHeaderValue) -> actix_web::Result<HttpResponse> {
     Ok(HttpResponse::SeeOther()
-        .header("location", path.as_ref()) // back - to where?
+        .header("location", path) // back - to where?
         .finish())
 }
 
+trait ParseOrBadReq {
+    fn parse_or_bad_request<T, E>(&self) -> actix_web::Result<T>
+    where T: FromStr<Err=E>,
+          E: Display + Debug + 'static;
+}
+
+impl ParseOrBadReq for &str {
+    fn parse_or_bad_request<T, E>(&self) -> actix_web::Result<T>
+        where T: FromStr<Err=E>,
+              E: Display + Debug + 'static
+    {
+        self.parse::<T>()
+            .map_err(|e| actix_web::error::ErrorBadRequest(e))
+    }
+}
+
+impl ParseOrBadReq for String {
+    fn parse_or_bad_request<T, E>(&self) -> actix_web::Result<T>
+        where T: FromStr<Err=E>,
+              E: Display + Debug + 'static
+    {
+        self.as_str()
+            .parse_or_bad_request()
+    }
+}
+
+
 #[get("/")]
 pub(crate) async fn index(session : Session, store : crate::YopaStoreWrapper) -> actix_web::Result<impl Responder> {
 
@@ -115,6 +145,70 @@ pub(crate) async fn object_model_create(
     }
 }
 
+#[get("/model/relation/create/{object_id}")]
+pub(crate) async fn relation_model_create_form(
+    object_id : web::Path<String>,
+    store : crate::YopaStoreWrapper,
+    session : Session
+) -> actix_web::Result<impl Responder> {
+    let mut context = tera::Context::new();
+    session.render_flash(&mut context);
+
+    let rg = store.read().await;
+
+    debug!("ID = {}", object_id);
+
+    let object = rg.get_object_model(object_id.parse_or_bad_request()?)
+        .ok_or_else(|| actix_web::error::ErrorNotFound("No such source object"))?;
+
+    let mut models: Vec<_> = rg.get_object_models().collect();
+
+    models.sort_by_key(|m| &m.name);
+
+    context.insert("models", &models);
+    context.insert("object", &object);
+
+    TERA.build_response("relation_create", &context)
+}
+
+#[derive(Deserialize)]
+pub(crate) struct RelationModelCreate {
+    pub object : ID,
+    pub name : String,
+    pub optional : Option<i32>,
+    pub multiple : Option<i32>,
+    pub related : ID,
+}
+
+#[post("/model/relation/create")]
+pub(crate) async fn relation_model_create(
+    form : web::Form<RelationModelCreate>,
+    store : crate::YopaStoreWrapper,
+    session : Session
+) -> actix_web::Result<impl Responder> {
+    let mut wg = store.write().await;
+    let form = form.into_inner();
+    match wg.define_relation(RelationModel {
+        id: Default::default(),
+        object: form.object,
+        name: form.name.clone(),
+        optional: form.optional.unwrap_or_default() != 0,
+        multiple: form.multiple.unwrap_or_default() != 0,
+        related: form.related
+    }) {
+        Ok(_id) => {
+            debug!("Relation created, redirecting to root");
+            session.flash_success(format!("Relation model \"{}\" created.", form.name));
+            redirect("/")
+        }
+        Err(e) => {
+            warn!("Error creating relation model: {:?}", e);
+            session.flash_error(e.to_string());
+            redirect(format!("/model/relation/create/{}", form.object))
+        }
+    }
+}
+
 #[get("/model/object/delete/{id}")]
 pub(crate) async fn object_model_delete(
     id : web::Path<String>,
@@ -143,7 +237,7 @@ pub(crate) async fn relation_model_delete(
     session : Session
 ) -> actix_web::Result<impl Responder> {
     let mut wg = store.write().await;
-    match wg.undefine_relation(id.parse().map_err(|e| actix_web::error::ErrorBadRequest(e))?) {
+    match wg.undefine_relation(id.parse_or_bad_request()?) {
         Ok(rm) => {
             debug!("Relation deleted, redirecting to root");
             session.flash_success(format!("Relation model \"{}\" deleted.", rm.name));
@@ -164,7 +258,7 @@ pub(crate) async fn property_model_delete(
     session : Session
 ) -> actix_web::Result<impl Responder> {
     let mut wg = store.write().await;
-    match wg.undefine_property(id.parse().map_err(|e| actix_web::error::ErrorBadRequest(e))?) {
+    match wg.undefine_property(id.parse_or_bad_request()?) {
         Ok(rm) => {
             debug!("Property deleted, redirecting to root");
             session.flash_success(format!("Property \"{}\" deleted.", rm.name));
diff --git a/yopa/src/lib.rs b/yopa/src/lib.rs
index f298d55..c8a5857 100644
--- a/yopa/src/lib.rs
+++ b/yopa/src/lib.rs
@@ -339,6 +339,18 @@ impl Storage {
         self.obj_models.values()
     }
 
+    pub fn get_object_model(&self, id : ID) -> Option<&ObjectModel> {
+        self.obj_models.get(&id)
+    }
+
+    pub fn get_relation_model(&self, id : ID) -> Option<&RelationModel> {
+        self.rel_models.get(&id)
+    }
+
+    pub fn get_prop_model(&self, id : ID) -> Option<&PropertyModel> {
+        self.prop_models.get(&id)
+    }
+
     pub fn get_grouped_prop_models(&self) -> HashMap<ID, Vec<&PropertyModel>> {
         self.prop_models.values()
             .into_group_map_by(|model| model.object)