diff --git a/src/ctlike/ctlike.cpp b/src/ctlike/ctlike.cpp
index d01661e..8dab2b0 100644
--- a/src/ctlike/ctlike.cpp
+++ b/src/ctlike/ctlike.cpp
@@ -25,6 +25,67 @@
 #include "GTools.hpp"
 
 
+/*==========================================================================
+ =                                                                         =
+ =                        Constructors/destructors                         =
+ =                                                                         =
+ ==========================================================================*/
+
+/***********************************************************************//**
+ * @brief Void constructor
+ ***************************************************************************/
+ctlike::ctlike(void) :  GApplication(CTLIKE_NAME, CTLIKE_VERSION)
+{
+    // Initialise members
+    init_members();
+
+    // Return
+    return;
+}
+
+
+/***********************************************************************//**
+ * @brief Command line constructor
+ *
+ * @param[in] argc Number of arguments in command line.
+ * @param[in] argv Array of command line arguments.
+ ***************************************************************************/
+ctlike::ctlike(int argc, char *argv[]) : 
+                        GApplication(CTLIKE_NAME, CTLIKE_VERSION, argc, argv)
+{
+    // Initialise members
+    init_members();
+
+    // Return
+    return;
+}
+
+
+/***********************************************************************//**
+ * @brief Destructor
+ ***************************************************************************/
+ctlike::~ctlike(void)
+{
+    // Free members
+    free_members();
+
+    // Return
+    return;
+}
+
+
+/*==========================================================================
+ =                                                                         =
+ =                               Operators                                 =
+ =                                                                         =
+ ==========================================================================*/
+
+/*==========================================================================
+ =                                                                         =
+ =                            Public methods                               =
+ =                                                                         =
+ ==========================================================================*/
+
 /***********************************************************************//**
  * @brief Run maximum likelihood analysis
  ***************************************************************************/
@@ -38,11 +99,11 @@ int ctlike::run(void)
     m_caldb  = par("caldb")->value();
     m_irf    = par("irf")->value();
     m_srcmdl = par("srcmdl")->value();
+    m_outmdl = par("outmdl")->value();
     m_models = GModels(m_srcmdl);
 
     // Set fixed parameters
-    m_max_iter = 1000;
-    m_opt      = new GOptimizerLM;
+    m_opt    = new GOptimizerLM;
 
     // Set optimizer parameters
     ((GOptimizerLM*)m_opt)->max_iter(m_max_iter);
@@ -53,6 +114,13 @@ int ctlike::run(void)
     else
         rc = binned();
 
+    // Write result as XML model
+    if (toupper(m_outmdl) != "NONE")
+        m_models.save(m_outmdl);
+
+    // Dump results
+    std::cout << m_models << std::endl;
+
     // Free optimizer
     delete m_opt;
 
@@ -73,7 +141,6 @@ int ctlike::unbinned(void)
     std::string evfile = par("evfile")->value();
 
     // Declare observations
-    GObservations   obs;
     GCTAObservation run;
 
     // Setup ROI covered by data
@@ -102,14 +169,16 @@ int ctlike::unbinned(void)
     run.roi(roi);
     run.gti()->add(tstart, tstop);
     run.ebounds()->append(emin, emax);
-    obs.append(run);
+    m_obs.append(run);
 
     // Setup models for optimizing
-    obs.models(m_models);
+    m_obs.models(m_models);
 
     // Perform LM optimization
-    obs.optimize(*m_opt);
-    std::cout << obs << std::endl;
+    m_obs.optimize(*m_opt);
+    
+    // Get models back
+    m_models = *(m_obs.models());
     
     // Return
     return rc;
@@ -128,21 +197,62 @@ int ctlike::binned(void)
     std::string cntmap = par("cntmap")->value();
 
     // Declare observations
-    GObservations   obs;
     GCTAObservation run;
 
     // Load binned CTA observation
     run.load_binned(cntmap);
     run.response(m_irf, m_caldb);
-    obs.append(run);
+    m_obs.append(run);
 
     // Setup models for optimizing
-    obs.models(m_models);
+    m_obs.models(m_models);
 
     // Perform LM optimization
-    obs.optimize(*m_opt);
-    std::cout << obs << std::endl;
+    m_obs.optimize(*m_opt);
+
+    // Get models back
+    m_models = *(m_obs.models());
 
     // Return
     return rc;
 }
+
+
+/*==========================================================================
+ =                                                                         =
+ =                             Private methods                             =
+ =                                                                         =
+ ==========================================================================*/
+
+/***********************************************************************//**
+ * @brief Initialise class members
+ ***************************************************************************/
+void ctlike::init_members(void)
+{
+    // Initialise members
+    m_method.clear();
+    m_caldb.clear();
+    m_irf.clear();
+    m_srcmdl.clear();
+    m_outmdl.clear();
+    m_models.clear();
+    //m_obs.clear();     //!< NOT YET IMPLEMENTED
+    m_max_iter = 1000;
+    m_opt      = NULL;
+
+    // Return
+    return;
+}
+
+
+/***********************************************************************//**
+ * @brief Delete class members
+ ***************************************************************************/
+void ctlike::free_members(void)
+{
+    // Free members
+    delete m_opt;
+
+    // Return
+    return;
+}
diff --git a/src/ctlike/ctlike.hpp b/src/ctlike/ctlike.hpp
index c016d58..2cc7ab0 100644
--- a/src/ctlike/ctlike.hpp
+++ b/src/ctlike/ctlike.hpp
@@ -37,10 +37,9 @@
 class ctlike : public GApplication  {
 public:
     // Constructors and destructors
-    ctlike(void) : 
-           GApplication(CTLIKE_NAME, CTLIKE_VERSION) { return; }
-    ctlike(int argc, char *argv[]) : 
-           GApplication(CTLIKE_NAME, CTLIKE_VERSION, argc, argv) { return; }
+    ctlike(void);
+    ctlike(int argc, char *argv[]);
+    ~ctlike(void);
 
     // Methods
     int run(void);
@@ -48,16 +47,22 @@ public:
     int binned(void);
 
 protected:
+    // Protected methods
+    void init_members(void);
+    void free_members(void);
+
     // User parameters
-    std::string m_method;     //!< Likelihood fitting method (binned/unbinned)
-    std::string m_caldb;      //!< Calibration database
-    std::string m_irf;        //!< Instrument response functions
-    std::string m_srcmdl;     //!< Source model XML file
-    GModels     m_models;     //!< Source models
+    std::string   m_method;     //!< Likelihood fitting method (binned/unbinned)
+    std::string   m_caldb;      //!< Calibration database
+    std::string   m_irf;        //!< Instrument response functions
+    std::string   m_srcmdl;     //!< Source model XML file
+    std::string   m_outmdl;     //!< Source model output XML file
+    GModels       m_models;     //!< Source models
+    GObservations m_obs;        //!< Observations
 
     // Fixed parameters
-    int         m_max_iter;   //!< Maximum number of iterations
-    GOptimizer* m_opt;        //!< Optimizer
+    int           m_max_iter;   //!< Maximum number of iterations
+    GOptimizer*   m_opt;        //!< Optimizer
 };
 
 #endif /* CTLIKE_HPP */