diff --git a/src/ordering/application/services/add_line_item_service.rs b/src/ordering/application/services/add_line_item_service.rs
new file mode 100644
index 0000000..75a7e4e
--- /dev/null
+++ b/src/ordering/application/services/add_line_item_service.rs
@@ -0,0 +1,113 @@
+// SPDX-FileCopyrightText: 2024 Aravinth Manivannan <realaravinth@batsense.net>
+//
+// SPDX-License-Identifier: AGPL-3.0-or-later
+
+use std::sync::Arc;
+
+use derive_builder::Builder;
+use mockall::predicate::*;
+use mockall::*;
+use time::OffsetDateTime;
+
+use super::errors::*;
+use crate::ordering::{
+    application::port::output::db::line_item_id_exists::*,
+    domain::{add_line_item_command::*, line_item_added_event::*, line_item_aggregate::*},
+};
+use crate::utils::uuid::*;
+
+#[automock]
+#[async_trait::async_trait]
+pub trait AddLineItemUseCase: Send + Sync {
+    async fn add_line_item(&self, cmd: AddLineItemCommand) -> OrderingResult<LineItemAddedEvent>;
+}
+
+pub type AddLineItemServiceObj = Arc<dyn AddLineItemUseCase>;
+
+#[derive(Clone, Builder)]
+pub struct AddLineItemService {
+    db_line_item_id_exists: LineItemIDExistsDBPortObj,
+    get_uuid: GetUUIDInterfaceObj,
+}
+
+#[async_trait::async_trait]
+impl AddLineItemUseCase for AddLineItemService {
+    async fn add_line_item(&self, cmd: AddLineItemCommand) -> OrderingResult<LineItemAddedEvent> {
+        let mut line_item_id = self.get_uuid.get_uuid();
+
+        loop {
+            if self
+                .db_line_item_id_exists
+                .line_item_id_exists(&line_item_id)
+                .await?
+            {
+                line_item_id = self.get_uuid.get_uuid();
+                continue;
+            } else {
+                break;
+            }
+        }
+
+        let line_item = LineItemBuilder::default()
+            .sale_time(OffsetDateTime::now_utc())
+            .product_name(cmd.product_name().into())
+            .product_id(*cmd.product_id())
+            .line_item_id(line_item_id)
+            .quantity(cmd.quantity().clone())
+            .deleted(false)
+            .build()
+            .unwrap();
+
+        Ok(LineItemAddedEventBuilder::default()
+            .added_by_user(*cmd.adding_by())
+            .line_item(line_item)
+            .build()
+            .unwrap())
+    }
+}
+
+#[cfg(test)]
+pub mod tests {
+    use super::*;
+
+    use crate::ordering::domain::line_item_added_event::tests::get_added_line_item_event_from_command;
+    use crate::utils::uuid::tests::UUID;
+    use crate::{tests::bdd::*, utils::uuid::tests::mock_get_uuid};
+
+    pub fn mock_add_line_item_service(
+        times: Option<usize>,
+        cmd: AddLineItemCommand,
+    ) -> AddLineItemServiceObj {
+        let mut m = MockAddLineItemUseCase::new();
+
+        let res = get_added_line_item_event_from_command(&cmd);
+        if let Some(times) = times {
+            m.expect_add_line_item()
+                .times(times)
+                .returning(move |_| Ok(res.clone()));
+        } else {
+            m.expect_add_line_item().returning(move |_| Ok(res.clone()));
+        }
+
+        Arc::new(m)
+    }
+
+    #[actix_rt::test]
+    async fn test_service() {
+        let cmd = AddLineItemCommand::get_cmd();
+
+        let s = AddLineItemServiceBuilder::default()
+            .db_line_item_id_exists(mock_line_item_id_exists_db_port_false(IS_CALLED_ONLY_ONCE))
+            .get_uuid(mock_get_uuid(IS_CALLED_ONLY_ONCE))
+            .build()
+            .unwrap();
+
+        let res = s.add_line_item(cmd.clone()).await.unwrap();
+        assert_eq!(res.line_item().product_name(), cmd.product_name());
+        assert_eq!(res.line_item().product_id(), cmd.product_id());
+        assert_eq!(res.line_item().quantity(), cmd.quantity());
+        assert_eq!(res.line_item().quantity(), cmd.quantity());
+        assert!(!res.line_item().deleted());
+        assert_eq!(res.added_by_user(), cmd.adding_by());
+    }
+}
diff --git a/src/ordering/application/services/errors.rs b/src/ordering/application/services/errors.rs
new file mode 100644
index 0000000..175d921
--- /dev/null
+++ b/src/ordering/application/services/errors.rs
@@ -0,0 +1,30 @@
+// SPDX-FileCopyrightText: 2024 Aravinth Manivannan <realaravinth@batsense.net>
+//
+// SPDX-License-Identifier: AGPL-3.0-or-later
+
+use derive_more::{Display, Error};
+use log::error;
+use serde::{Deserialize, Serialize};
+
+use crate::ordering::application::port::output::db::errors::OrderingDBError;
+
+pub type OrderingResult<V> = Result<V, OrderingError>;
+
+#[derive(Debug, Error, Display, Clone, Serialize, Deserialize, PartialEq, Eq, PartialOrd, Ord)]
+pub enum OrderingError {
+    LineItemIDNotFound,
+    InternalError,
+}
+//
+impl From<OrderingDBError> for OrderingError {
+    fn from(value: OrderingDBError) -> Self {
+        match value {
+            OrderingDBError::DuplicateLineItemID => {
+                error!("DuplicateLineItemID");
+                Self::InternalError
+            }
+            OrderingDBError::LineItemIDNotFound => OrderingError::LineItemIDNotFound,
+            OrderingDBError::InternalError => Self::InternalError,
+        }
+    }
+}
diff --git a/src/ordering/application/services/mod.rs b/src/ordering/application/services/mod.rs
index 56f60de..ac7dd23 100644
--- a/src/ordering/application/services/mod.rs
+++ b/src/ordering/application/services/mod.rs
@@ -1,3 +1,28 @@
 // SPDX-FileCopyrightText: 2024 Aravinth Manivannan <realaravinth@batsense.net>
 //
 // SPDX-License-Identifier: AGPL-3.0-or-later
+
+use derive_builder::Builder;
+use mockall::predicate::*;
+use mockall::*;
+
+pub mod errors;
+
+//services
+pub mod add_line_item_service;
+
+#[automock]
+pub trait OrderingServicesInterface: Send + Sync {
+    fn add_line_item(&self) -> add_line_item_service::AddLineItemServiceObj;
+}
+
+#[derive(Clone, Builder)]
+pub struct OrderingServices {
+    add_line_item: add_line_item_service::AddLineItemServiceObj,
+}
+
+impl OrderingServicesInterface for OrderingServices {
+    fn add_line_item(&self) -> add_line_item_service::AddLineItemServiceObj {
+        self.add_line_item.clone()
+    }
+}