diff --git a/src/api3.rs b/src/api3.rs
index 96fb5bf4..9dbb5938 100644
--- a/src/api3.rs
+++ b/src/api3.rs
@@ -34,7 +34,7 @@ pub fn router() -> MethodInfo {
             description: "This is a simple test.",
             parameters: parameter!{
                 force => Boolean!{
-                    optional => Some(true),
+                    optional => true,
                     description => "Test for boolean options."
                 }
             },
diff --git a/src/json_schema.rs b/src/json_schema.rs
index 69d59dfa..2af76b38 100644
--- a/src/json_schema.rs
+++ b/src/json_schema.rs
@@ -7,23 +7,23 @@ pub type PropertyMap = HashMap<&'static str, Jss>;
 #[derive(Debug)]
 pub struct JssBoolean {
     pub description: &'static str,
-    pub optional: Option<bool>,
+    pub optional: bool,
     pub default: Option<bool>,
 }
 
 #[derive(Debug)]
 pub struct JssInteger {
     pub description: &'static str,
-    pub optional: Option<bool>,
-    pub minimum: Option<usize>,
-    pub maximum: Option<usize>,
-    pub default: Option<usize>,
+    pub optional: bool,
+    pub minimum: Option<isize>,
+    pub maximum: Option<isize>,
+    pub default: Option<isize>,
 }
 
 #[derive(Debug)]
 pub struct JssString {
     pub description: &'static str,
-    pub optional: Option<bool>,
+    pub optional: bool,
     pub default: Option<&'static str>,
     pub min_length: Option<usize>,
     pub max_length: Option<usize>,
@@ -32,15 +32,15 @@ pub struct JssString {
 #[derive(Debug)]
 pub struct JssArray {
     pub description: &'static str,
-    pub optional: Option<bool>,
+    pub optional: bool,
     pub items: Box<Jss>,
 }
 
 #[derive(Debug)]
 pub struct JssObject {
     pub description: &'static str,
-    pub optional: Option<bool>,
-    pub additional_properties: Option<bool>,
+    pub optional: bool,
+    pub additional_properties: bool,
     pub properties: HashMap<&'static str, Jss>,
 }
 
@@ -56,7 +56,7 @@ pub enum Jss {
 
 pub const DEFAULTBOOL: JssBoolean = JssBoolean {
     description: "",
-    optional: None,
+    optional: false,
     default: None,
 };
 
@@ -69,7 +69,7 @@ macro_rules! Boolean {
 
 pub const DEFAULTINTEGER: JssInteger = JssInteger {
     description: "",
-    optional: None,
+    optional: false,
     default: None,
     minimum: None,
     maximum: None,
@@ -84,7 +84,7 @@ macro_rules! Integer {
 
 pub const DEFAULTSTRING: JssString = JssString {
     description: "",
-    optional: None,
+    optional: false,
     default: None,
     min_length: None,
     max_length: None,
@@ -102,8 +102,8 @@ macro_rules! parameter {
     ($($name:ident => $e:expr),*) => {{
         let inner = JssObject {
             description: "",
-            optional: None,
-            additional_properties: None,
+            optional: false,
+            additional_properties: false,
             properties: {
                 let mut map = HashMap::<&'static str, Jss>::new();
                 $(
@@ -117,12 +117,106 @@ macro_rules! parameter {
     }}
 }
 
+fn parse_simple_value(value_str: &str, schema: &Jss) -> Result<Value, Error> {
 
-pub fn parse_parameter_strings(data: &Vec<(String, String)>, schema: &Jss) -> Result<Value, Error> {
+    let value = match schema {
+        Jss::Null => {
+            bail!("parse_parameter_strings: internal error - schema contains Null.");
+        }
+        Jss::Boolean(jss_boolean) => {
+            let res = match value_str.to_lowercase().as_str() {
+                "1" | "on" | "yes" | "true" => true,
+                "0" | "off" | "no" | "false" => false,
+                _ => bail!("Unable to parse boolean option."),
+            };
+            Value::Bool(res)
+        }
+        Jss::Integer(jss_integer) => {
+            let res: isize = value_str.parse()?;
+            Value::Number(res.into())
+        }
+        Jss::String(jss_string) => {
+            Value::String(value_str.into())
+        }
+        _ => bail!("parse_simple_value: schema contains complex Objects."),
+    };
+    Ok(value)
+}
+
+pub fn parse_parameter_strings(data: &Vec<(String, String)>, schema: &Jss) -> Result<Value, Vec<Error>> {
 
     println!("QUERY Strings {:?}", data);
 
-    Ok(json!(null))
+    let mut params = json!({});
+
+    let mut errors: Vec<Error> = Vec::new();
+
+    match schema {
+        Jss::Object(JssObject { properties, additional_properties, .. })   => {
+            for (key, value) in data {
+                if let Some(prop_schema) = properties.get::<str>(key) {
+                    match prop_schema {
+                        Jss::Object(_) => {
+                            errors.push(format_err!("parameter {}: cant parse complex Objects.", key));
+                        }
+                        Jss::Array(jss_array) => {
+                            if params[key] == Value::Null {
+                                params[key] = json!([]);
+                            }
+                            match params[key] {
+                                Value::Array(ref mut array) => {
+                                    match parse_simple_value(value, &jss_array.items) {
+                                        Ok(res) => array.push(res),
+                                        Err(err) => errors.push(format_err!("parameter {}: {}", key, err)),
+                                    }
+                                }
+                                _ => errors.push(format_err!("parameter {}: expected array - type missmatch", key)),
+                            }
+                        }
+                        _ => {
+                            match parse_simple_value(value, prop_schema) {
+                                Ok(res) => {
+                                    if params[key] == Value::Null {
+                                        params[key] = res;
+                                    } else {
+                                         errors.push(format_err!("parameter {}: duplicate parameter.", key));
+                                    }
+                                },
+                                Err(err) => errors.push(format_err!("parameter {}: {}", key, err)),
+                            }
+                        }
+
+                    }
+                } else {
+                    if *additional_properties {
+                        match params[key] {
+                            Value::Null => {
+                                params[key] = Value::String(value.to_owned());
+                            },
+                            Value::String(ref old) => {
+                                params[key] = Value::Array(
+                                    vec![Value::String(old.to_owned()),  Value::String(value.to_owned())]);
+                            }
+                            Value::Array(ref mut array) => {
+                                array.push(Value::String(value.to_string()));
+                            }
+                            _ => errors.push(format_err!("parameter {}: expected array - type missmatch", key)),
+                        }
+                    } else {
+                        errors.push(format_err!("parameter {}: schema does not allow additional properties.", key));
+                    }
+                }
+            }
+        }
+        _ => errors.push(format_err!("Got unexpected schema type in parse_parameter_strings.")),
+
+    }
+
+    if (errors.len() > 0) {
+        Err(errors)
+    } else {
+        Ok(params)
+    }
 }
 
 #[test]
diff --git a/src/main.rs b/src/main.rs
index 6213f357..04e4014a 100644
--- a/src/main.rs
+++ b/src/main.rs
@@ -70,7 +70,13 @@ fn handle_request(req: Request<Body>) -> Response<Body> {
 
                         match parse_parameter_strings(&param_list, &api_method.parameters) {
                             Ok(query) => query,
-                            Err(err) => http_error!(NOT_FOUND, format!("Unable to parse query parameters '{}' - {}", data, err)),
+                            Err(ref error_list) => {
+                                let mut msg = String::from("");
+                                for item in error_list {
+                                    msg = msg + &item.to_string() + "\n";
+                                }
+                                http_error!(BAD_REQUEST, msg);
+                            }
                         }
                     }
                     None => json!({}),