diff --git a/ComunicMessages.pro b/ComunicMessages.pro
index 5723ac6..a8089e9 100644
--- a/ComunicMessages.pro
+++ b/ComunicMessages.pro
@@ -26,7 +26,9 @@ SOURCES += \
     utils/uiutils.cpp \
     data/userslist.cpp \
     utils/timeutils.cpp \
-    widgets/conversationwidget.cpp
+    widgets/conversationwidget.cpp \
+    data/newconversationmessage.cpp \
+    helpers/conversationhelper.cpp
 
 HEADERS += \
     helpers/accounthelper.h \
@@ -54,7 +56,9 @@ HEADERS += \
     utils/uiutils.h \
     data/userslist.h \
     utils/timeutils.h \
-    widgets/conversationwidget.h
+    widgets/conversationwidget.h \
+    data/newconversationmessage.h \
+    helpers/conversationhelper.h
 
 FORMS += \
     widgets/loginwidget.ui \
diff --git a/config.h b/config.h
index 6e80e0d..20565aa 100644
--- a/config.h
+++ b/config.h
@@ -29,4 +29,9 @@
 #define SETTINGS_ACCOUNT_LOGIN_TOKEN_1 "account_login_token_1"
 #define SETTINGS_ACCOUNT_LOGIN_TOKEN_2 "account_login_token_2"
 
+/**
+ * Conversations information
+ */
+#define CONVERSATION_MESSAGE_MIN_LENGTH 3
+
 #endif // CONFIG_H
diff --git a/data/newconversationmessage.cpp b/data/newconversationmessage.cpp
new file mode 100644
index 0000000..ee81c1c
--- /dev/null
+++ b/data/newconversationmessage.cpp
@@ -0,0 +1,26 @@
+#include "newconversationmessage.h"
+
+NewConversationMessage::NewConversationMessage()
+{
+
+}
+
+int NewConversationMessage::iDConversation() const
+{
+    return mIDConversation;
+}
+
+void NewConversationMessage::setIDConversation(int iDConversation)
+{
+    mIDConversation = iDConversation;
+}
+
+QString NewConversationMessage::message() const
+{
+    return mMessage;
+}
+
+void NewConversationMessage::setMessage(const QString &message)
+{
+    mMessage = message;
+}
diff --git a/data/newconversationmessage.h b/data/newconversationmessage.h
new file mode 100644
index 0000000..fd6e530
--- /dev/null
+++ b/data/newconversationmessage.h
@@ -0,0 +1,30 @@
+/**
+ * New conversation message
+ *
+ * Contains information about a message to send
+ * to the server
+ *
+ * @author Pierre HUBERT
+ */
+#ifndef NEWCONVERSATIONMESSAGE_H
+#define NEWCONVERSATIONMESSAGE_H
+
+#include <QString>
+
+class NewConversationMessage
+{
+public:
+    NewConversationMessage();
+
+    int iDConversation() const;
+    void setIDConversation(int iDConversation);
+
+    QString message() const;
+    void setMessage(const QString &message);
+
+private:
+    int mIDConversation;
+    QString mMessage;
+};
+
+#endif // NEWCONVERSATIONMESSAGE_H
diff --git a/helpers/conversationhelper.cpp b/helpers/conversationhelper.cpp
new file mode 100644
index 0000000..870a354
--- /dev/null
+++ b/helpers/conversationhelper.cpp
@@ -0,0 +1,33 @@
+#include "apihelper.h"
+#include "conversationhelper.h"
+#include "../data/apirequest.h"
+
+ConversationHelper::ConversationHelper(QObject *parent) : QObject(parent)
+{
+    mAPIHelper = new APIHelper(this);
+}
+
+void ConversationHelper::sendMessage(const NewConversationMessage &message)
+{
+    APIRequest *request = new APIRequest;
+    request->setURI("conversations/sendMessage");
+    request->addInt("conversationID", message.iDConversation());
+    request->addString("message", message.message());
+
+    connect(request, &APIRequest::finished, this, &ConversationHelper::sendMessageFinished);
+    mAPIHelper->execute(request);
+}
+
+void ConversationHelper::sendMessageFinished(int code)
+{
+    //Delete sender
+    qobject_cast<APIRequest *>(sender())->deleteLater();
+
+    if(code != 200){
+        emit sendMessageCallback(false);
+        return;
+    }
+
+    //Success
+    emit sendMessageCallback(true);
+}
diff --git a/helpers/conversationhelper.h b/helpers/conversationhelper.h
new file mode 100644
index 0000000..5536250
--- /dev/null
+++ b/helpers/conversationhelper.h
@@ -0,0 +1,61 @@
+/**
+ * Conversation helper
+ *
+ * This class is an interface between the server
+ * and the conversations widgets
+ *
+ * @author Pierre HUBERT
+ */
+#ifndef CONVERSATIONHELPER_H
+#define CONVERSATIONHELPER_H
+
+#include <QObject>
+
+#include "../data/newconversationmessage.h"
+#include "../data/apirequest.h"
+
+class APIHelper;
+
+class ConversationHelper : public QObject
+{
+    Q_OBJECT
+public:
+    explicit ConversationHelper(QObject *parent = nullptr);
+
+    /**
+     * Send a message to the server
+     *
+     * @param message Information about the message to send
+     */
+    void sendMessage(const NewConversationMessage &message);
+
+signals:
+
+    /**
+     * This signal is emitted when we have got the result of a create message
+     * attempt
+     *
+     * @param success TRUE if the operation is a success / FALSE
+     */
+    void sendMessageCallback(bool success);
+
+public slots:
+
+
+private slots:
+
+    /**
+     * Send message callback
+     *
+     * @param code The code of the error
+     * @param & Server response (useless in this case)
+     */
+    void sendMessageFinished(int code);
+
+private:
+
+    //Private fields
+    APIHelper *mAPIHelper;
+};
+
+#endif // CONVERSATIONHELPER_H
diff --git a/widgets/conversationwidget.cpp b/widgets/conversationwidget.cpp
index 148864a..00f89e0 100644
--- a/widgets/conversationwidget.cpp
+++ b/widgets/conversationwidget.cpp
@@ -1,6 +1,10 @@
+#include <QMessageBox>
+
 #include "conversationwidget.h"
 #include "ui_conversationwidget.h"
 #include "../helpers/conversationslisthelper.h"
+#include "../helpers/conversationhelper.h"
+#include "../config.h"
 
 ConversationWidget::ConversationWidget(const Conversation &conversation, const UsersList &list, QWidget *parent) :
     QWidget(parent),
@@ -13,6 +17,10 @@ ConversationWidget::ConversationWidget(const Conversation &conversation, const U
     //Initialize UI
     QString convTitle = ConversationsListHelper::getConversationDisplayName(conversation, list);
     ui->convName->setText(convTitle);
+
+    //Initalize helpers
+    mConversationHelper = new ConversationHelper(this);
+    connect(mConversationHelper, &ConversationHelper::sendMessageCallback, this, &ConversationWidget::sendMessageCallback);
 }
 
 ConversationWidget::~ConversationWidget()
@@ -22,7 +30,42 @@ ConversationWidget::~ConversationWidget()
 
 void ConversationWidget::sendMessage()
 {
-    qWarning("Send a new message");
+    if(isSendMessageFormLocked()){
+        qInfo("sendMessage cancelled because another send message request is running...");
+        return;
+    }
+
+    QString content = ui->messageContentInput->text();
+
+    //Check message length
+    if(content.length() < CONVERSATION_MESSAGE_MIN_LENGTH){
+        QMessageBox::warning(this, tr("Invalid message!"), tr("Specified message is too short!"));
+        return;
+    }
+
+    //Lock send form
+    setSendMessageFormLocked(true);
+
+    //Send a request to send message
+    NewConversationMessage newMessage;
+    newMessage.setIDConversation(mConversation.iD());
+    newMessage.setMessage(content);
+
+    //Request the message to be sent
+    mConversationHelper->sendMessage(newMessage);
+}
+
+void ConversationWidget::sendMessageCallback(bool success)
+{
+    setSendMessageFormLocked(false);
+
+    if(!success){
+        QMessageBox::warning(this, tr("Error"), tr("Could not send your message! Please check it and your Internet connection..."));
+        return;
+    }
+
+    //Reset message form
+    resetSendMessageForm();
 }
 
 void ConversationWidget::on_sendMessageButton_clicked()
@@ -34,3 +77,19 @@ void ConversationWidget::on_messageContentInput_returnPressed()
 {
     sendMessage();
 }
+
+void ConversationWidget::setSendMessageFormLocked(bool lock)
+{
+    ui->sendMessageButton->setEnabled(!lock);
+    ui->messageContentInput->setEnabled(!lock);
+}
+
+bool ConversationWidget::isSendMessageFormLocked()
+{
+    return !ui->sendMessageButton->isEnabled();
+}
+
+void ConversationWidget::resetSendMessageForm()
+{
+    ui->messageContentInput->setText("");
+}
diff --git a/widgets/conversationwidget.h b/widgets/conversationwidget.h
index a75209d..1dd9a6e 100644
--- a/widgets/conversationwidget.h
+++ b/widgets/conversationwidget.h
@@ -18,6 +18,8 @@ namespace Ui {
 class ConversationWidget;
 }
 
+class ConversationHelper;
+
 class ConversationWidget : public QWidget
 {
     Q_OBJECT
@@ -36,14 +38,32 @@ public slots:
 
 
 private slots:
+
+    /**
+     * Method called once the server replied to a send conversation
+     * message request
+     *
+     * @param success TRUE in case of success / FALSE else
+     */
+    void sendMessageCallback(bool success);
+
     void on_sendMessageButton_clicked();
 
     void on_messageContentInput_returnPressed();
 
 private:
 
+    /**
+     * Methods to get and set send message form
+     * lock state
+     */
+    void setSendMessageFormLocked(bool lock);
+    bool isSendMessageFormLocked();
+    void resetSendMessageForm();
+
     //Private fields
     Ui::ConversationWidget *ui;
+    ConversationHelper *mConversationHelper;
     Conversation mConversation;
     UsersList mUsersList;
 };