diff --git a/wfassoc-exec/src/manifest.rs b/wfassoc-exec/src/manifest.rs
index c206b8a..28f0496 100644
--- a/wfassoc-exec/src/manifest.rs
+++ b/wfassoc-exec/src/manifest.rs
@@ -62,14 +62,37 @@ impl Manifest {
 /// Error occurs when parsing manifest into schema.
 #[derive(Debug, TeError)]
 pub enum ParseSchemaError {
-    
+    /// Error when operating with schema.
+    #[error("{0}")]
+    Schema(#[from] wfassoc::highlevel::SchemaError)
 }
 
 impl TryFrom<Manifest> for wfassoc::Schema {
     type Error = ParseSchemaError;
 
-    fn try_from(value: Manifest) -> std::result::Result<Self, Self::Error> {
-        todo!()
+    fn try_from(value: Manifest) -> Result<Self, Self::Error> {
+        let mut schema = wfassoc::Schema::new();
+        
+        schema.set_identifier(&value.identifier);
+        schema.set_path(&value.path);
+        schema.set_clsid(&value.clsid);
+        schema.set_name(value.name.as_ref().map(|x| x.as_str()));
+        schema.set_icon(value.icon.as_ref().map(|x| x.as_str()));
+        schema.set_behavior(value.behavior.as_ref().map(|x| x.as_str()));
+        for (key, value) in value.strs {
+            schema.add_str(&key, &value)?;
+        }
+        for (key, value) in value.icons {
+            schema.add_icon(&key, &value)?;
+        }
+        for (key, value) in value.behaviors {
+            schema.add_behavior(&key, &value)?;
+        }
+        for (key, value) in value.exts {
+            schema.add_ext(&key, &value.name, &value.icon, &value.behavior)?;
+        }
+
+        Ok(schema)
     }
 }
 
diff --git a/wfassoc/src/highlevel.rs b/wfassoc/src/highlevel.rs
index dc0e7aa..5f6493d 100644
--- a/wfassoc/src/highlevel.rs
+++ b/wfassoc/src/highlevel.rs
@@ -8,7 +8,10 @@ pub use lowlevel::{Scope, View};
 
 /// Error occurs when operating with `Schema`.
 #[derive(Debug, TeError)]
-pub enum SchemaError {}
+pub enum SchemaError {
+    #[error("duplicate key: {0}")]
+    DuplicateKey(String),
+}
 
 /// Error occurs when trying converting `Schema` into `Program`.
 #[derive(Debug, TeError)]
@@ -40,14 +43,6 @@ pub struct Schema {
     exts: HashMap<String, SchemaExt>,
 }
 
-/// Internal used struct as the Schema file extensions hashmap value type.
-#[derive(Debug)]
-struct SchemaExt {
-    name: String,
-    icon: String,
-    behavior: String,
-}
-
 impl Schema {
     pub fn new() -> Self {
         Self {
@@ -64,24 +59,49 @@ impl Schema {
         }
     }
 
-    pub fn set_identifier(&mut self, identifier: &str) -> Result<(), SchemaError> {
-        todo!()
+    pub fn set_identifier(&mut self, identifier: &str) -> () {
+        self.identifier = identifier.to_string();
     }
 
-    pub fn set_path(&mut self, exe_path: &str) -> Result<(), SchemaError> {
-        todo!()
+    pub fn set_path(&mut self, exe_path: &str) -> () {
+        self.path = exe_path.to_string();
     }
 
-    pub fn set_clsid(&mut self, clsid: &str) -> Result<(), SchemaError> {
-        todo!()
+    pub fn set_clsid(&mut self, clsid: &str) -> () {
+        self.clsid = clsid.to_string();
+    }
+
+    pub fn set_name(&mut self, name: Option<&str>) -> () {
+        self.name = name.map(|n| n.to_string());
+    }
+
+    pub fn set_icon(&mut self, icon: Option<&str>) -> () {
+        self.icon = icon.map(|i| i.to_string());
+    }
+
+    pub fn set_behavior(&mut self, behavior: Option<&str>) -> () {
+        self.behavior = behavior.map(|b| b.to_string());
+    }
+
+    pub fn add_str(&mut self, name: &str, value: &str) -> Result<(), SchemaError> {
+        match self.strs.insert(name.to_string(), value.to_string()) {
+            Some(_) => Err(SchemaError::DuplicateKey(name.to_string())),
+            None => Ok(()),
+        }
     }
 
     pub fn add_icon(&mut self, name: &str, value: &str) -> Result<(), SchemaError> {
-        todo!()
+        match self.icons.insert(name.to_string(), value.to_string()) {
+            Some(_) => Err(SchemaError::DuplicateKey(name.to_string())),
+            None => Ok(()),
+        }
     }
 
     pub fn add_behavior(&mut self, name: &str, value: &str) -> Result<(), SchemaError> {
-        todo!()
+        match self.behaviors.insert(name.to_string(), value.to_string()) {
+            Some(_) => Err(SchemaError::DuplicateKey(name.to_string())),
+            None => Ok(()),
+        }
     }
 
     pub fn add_ext(
@@ -91,7 +111,13 @@ impl Schema {
         ext_icon: &str,
         ext_behavior: &str,
     ) -> Result<(), SchemaError> {
-        todo!()
+        match self.exts.insert(
+            ext.to_string(),
+            SchemaExt::new(ext_name, ext_icon, ext_behavior),
+        ) {
+            Some(_) => Err(SchemaError::DuplicateKey(ext.to_string())),
+            None => Ok(()),
+        }
     }
 
     pub fn into_program(self) -> Result<Program, ParseProgramError> {
@@ -99,6 +125,24 @@ impl Schema {
     }
 }
 
+/// Internal used struct as the Schema file extensions hashmap value type.
+#[derive(Debug)]
+struct SchemaExt {
+    name: String,
+    icon: String,
+    behavior: String,
+}
+
+impl SchemaExt {
+    fn new(name: &str, icon: &str, behavior: &str) -> Self {
+        Self {
+            name: name.to_string(),
+            icon: icon.to_string(),
+            behavior: behavior.to_string(),
+        }
+    }
+}
+
 /// Program is a complete and immutable program representer
 pub struct Program {}