diff --git a/missions/example_template/mission.yaml b/missions/example_template/mission.yaml
index 33da786..c6dbc2d 100644
--- a/missions/example_template/mission.yaml
+++ b/missions/example_template/mission.yaml
@@ -13,7 +13,8 @@ mission_file:
         altitude_origin: 0.0
 
 entities:
-    - template: entity.template.xml
+    - type: uav
+      template: entity.template.xml
       config: 
           id: 1
           x: -10
@@ -21,7 +22,8 @@ entities:
           z: 20
           heading: 270
           
-    - template: entity.template.xml
+    - type: uav
+      template: entity.template.xml
       config: 
           id: 2
           x: 10
@@ -29,7 +31,8 @@ entities:
           z: 10
           heading: 0
 
-    - template: entity.template.xml
+    - type: uav
+      template: entity.template.xml
       config: 
           id: 5
           x: -10
diff --git a/src/scrimmage_ros/EntityLaunch.py b/src/scrimmage_ros/EntityLaunch.py
index 63e8712..ee8fc9d 100644
--- a/src/scrimmage_ros/EntityLaunch.py
+++ b/src/scrimmage_ros/EntityLaunch.py
@@ -1,51 +1,92 @@
 #!/usr/bin/env python
 
 import os
+import yaml
 from jinja2 import Template
 
 import scrimmage_ros.MultiProcessLogger as MPL
 import scrimmage_ros.SimFilesGenerator as SFG
 import scrimmage_ros.utils as sru
 
-def get_name_command(process, entity_id):
-    name_t = Template(process['name'])
+def get_name_command(process_info, entity_id):
+    name_t = Template(process_info['name'])
     name = name_t.render(id=entity_id)
 
-    cmd_t = Template(process['command'])
+    cmd_t = Template(process_info['command'])
     cmd = cmd_t.render(id=entity_id)
 
     return name, cmd
 
+def create_process(process_info, entity_id, output_dir, env, console, terminal):
+    # Allow user to specify a post delay for a process
+    try:
+        post_delay = process_info['post_delay']
+    except:
+        post_delay = 0
+
+    # Allow the user to append the environment with additional variables
+    try:
+        environment = process_info['environment']
+    except:
+        environment = dict()
+    env.update(environment)
+
+    # Allow the user to change whether to write to the console or not
+    try:
+        console = process_info['console']
+    except:
+        # Don't override console type
+        pass
+
+    # Allow the user to change the terminal type
+    try:
+        terminal = MPL.Terminal(process_info['terminal'])
+    except:
+        # Use the default terminal
+        pass
+
+    # Perform template substitution based on entity_id {{ id }}
+    name, command = get_name_command(process_info, entity_id)
+
+    return {
+        'command': command,
+        'env': env,
+        'console': console,
+        'terminal': terminal,
+        'file': output_dir + '/%s.log' % name,
+        'post_delay': post_delay
+    }
+
 class EntityLaunch():
-    def __init__(self, mission_yaml_filename, output_dir, ros_package_name,
-                 launch_filename, launch_args='team_id:=1 entity_id:={{ id }}',
-                 entity_ids=None, terminal=MPL.Terminal.gnome,
-                 processes_per_entity=[], clean_up_processes_per_entity=[],
-                 clean_up_processes=[]):
+    def __init__(self, mission_yaml_filename, processess_yaml_file,
+                 output_dir,  entity_ids=None, entity_type=None):
+        self.entity_ids = entity_ids
+
         # The list of processes to pass to MultiProcessLogger
         self.processes = []
         self.clean_up_processes = []
 
-        self._mpl = MPL.MultiProcessLogger()
+        # Get the full path to the processes yaml file (ros find substitution)
+        processes_yaml_file_path = sru.ros_find_path(processess_yaml_file)
 
-        env = os.environ.copy()
+        # Parse the processes file
+        with open(processes_yaml_file_path) as f:
+             self._processes_yaml = yaml.load(f, Loader=yaml.FullLoader)
 
-        env['HOME'] = sru.user_home()
+        self.parse_defaults()
 
-        # Ensures that python prints and logs are displayed to screen
-        env['PYTHONUNBUFFERED'] = '1'
-
-        # Append the roscore process
-        self.processes.append(
-            { 'command': "roscore",
-              'env': env,
-              'console': True,
-              'file': output_dir + '/roscore.log',
-              'post_delay': 1.5
-            }
-        )
-
-        if entity_ids is None:
+        # Get processes that are run before entities
+        try:
+            processes_list = self._processes_yaml['processes']
+        except:
+            processes_list = []
+
+        # Append the processes that are run before entities
+        for p in processes_list:
+            self.processes.append(create_process(p, 0, output_dir, self.env, True, self.terminal))
+
+        # If the entity_ids is none, use scrimmage to run a simulation
+        if self.entity_ids is None:
             # Generate the scrimmage mission file and scrimmage file
             sfg = SFG.SimFilesGenerator(mission_yaml_filename, output_dir)
 
@@ -55,61 +96,90 @@ def __init__(self, mission_yaml_filename, output_dir, ros_package_name,
             # Append the scrimmage process
             self.processes.append(
                 { 'command': "scrimmage %s" % sfg.mission_file_path,
-                  'env': env,
+                  'env': self.env,
                   'console': True,
-                  'terminal': terminal,
+                  'terminal': self.terminal,
                   'file': output_dir + '/scrimmage.log',
                 }
             )
 
+        # Create a mapping of entity type to process infos
+        entity_type_to_processes = dict()
+        for entity_type_processes in self._processes_yaml['entity_processes']:
+            entity_type = entity_type_processes['type']
+            entity_type_to_processes[entity_type] = entity_type_processes
+
         # Append the processes for each entity's roslaunch
         for entity_id in self.entity_ids:
-            args_t = Template(launch_args)
-            args = args_t.render(id=entity_id)
+            # Get the entity type:
+            entity_type = sfg.entity_id_to_type(entity_id)
 
-            self.processes.append(
-                { 'command': sru.ros_launch(ros_package_name, launch_filename, args),
-                  'env': env,
-                  'console': True,
-                  'terminal': terminal,
-                  'file': output_dir + '/entity%d/entity.log' % entity_id
-                }
-            )
+            # Get the entity processes for this type
+            try:
+                entity_processes = entity_type_to_processes[entity_type]['processes']
+            except:
+                entity_processes = []
 
-            # The user can pass in additional processes to run per entity
-            for process in processes_per_entity:
-                name, cmd = get_name_command(process, entity_id)
-
-                self.processes.append(
-                    { 'command': cmd,
-                      'env': env,
-                      'console': True,
-                      'terminal': terminal,
-                      'file': output_dir + '/entity%d/%s.log' % (entity_id, name)
-                    }
-                )
-
-            # Append the cleanup processes that are associated with each entity
-            for process in clean_up_processes_per_entity:
-                name, cmd = get_name_command(process, entity_id)
-                self.clean_up_processes.append(
-                    {
-                        'command': cmd,
-                        'env': env,
-                    }
-                )
+            # Append the entity processes to the processes list
+            for p in entity_processes:
+                self.processes.append(create_process(p, entity_id, output_dir, self.env, True, self.terminal))
+
+            # Get the clean up processes for this type
+            try:
+                entity_clean_up_processes = entity_type_to_processes[entity_type]['clean_up']
+            except:
+                entity_clean_up_processes = []
+
+            # Append the clean up processes for this entity to the clean up list
+            for p in entity_clean_up_processes:
+                self.clean_up_processes.append(create_process(p, entity_id, output_dir, self.env, True, self.terminal))
 
         # Append the cleanup processes that apply to all entities
-        for process in clean_up_processes:
-            name, cmd = get_name_command(process, 0)
-            self.clean_up_processes.append(
-                {
-                    'command': cmd,
-                    'env': env,
-                }
-            )
+        try:
+            clean_up_process_infos = self._processes_yaml['clean_up']
+        except:
+            clean_up_process_infos = []
+
+        try:
+            for p in clean_up_process_infos:
+                self.clean_up_processes.append(create_process(p, 0, output_dir, self.env, True, self.terminal))
+        except:
+            pass
+
+    def parse_defaults(self):
+        # Parse the defaults block
+        try:
+            self.terminal = MPL.Terminal(self._processes_yaml['defaults']['terminal'])
+        except:
+            self.terminal=MPL.Terminal.gnome
+
+        # Get environment variables to append to current environment
+        try:
+            environment = self._processes_yaml['defaults']['environment']
+        except:
+            environment = dict()
+
+        # Environment setup
+        self.env = os.environ.copy()
+        self.env['HOME'] = sru.user_home()
 
+        # Ensures that python prints and logs are displayed to screen
+        self.env['PYTHONUNBUFFERED'] = '1'
+
+        # Append user-defined environment variables
+        self.env.update(environment)
+
+    def print_processes(self):
+        print('---------- Processes ------------')
+        for p in self.processes:
+            print(p['command'])
+
+        print('---------- Clean up ------------')
+        for p in self.clean_up_processes:
+            print(p['command'])
 
     def run(self):
+        mpl = MPL.MultiProcessLogger()
+
         # Run the processes. Blocking.
-        self._mpl.run(self.processes, self.clean_up_processes)
+        mpl.run(self.processes, self.clean_up_processes)
diff --git a/src/scrimmage_ros/MultiProcessLogger.py b/src/scrimmage_ros/MultiProcessLogger.py
index e6c80b8..c355dbc 100644
--- a/src/scrimmage_ros/MultiProcessLogger.py
+++ b/src/scrimmage_ros/MultiProcessLogger.py
@@ -148,5 +148,4 @@ def run(self, process_info, clean_up_processes=[]):
         if len(clean_up_processes) > 0:
             print('Running cleanup processes...')
             for process in clean_up_processes:
-                print(process['command'])
                 call(process['command'].split())
diff --git a/src/scrimmage_ros/SimFilesGenerator.py b/src/scrimmage_ros/SimFilesGenerator.py
index ee43542..eed9a73 100644
--- a/src/scrimmage_ros/SimFilesGenerator.py
+++ b/src/scrimmage_ros/SimFilesGenerator.py
@@ -53,10 +53,11 @@ def __init__(self, mission_yaml_file, output_dir):
         with open(self.mission_file_path, 'w') as f:
             f.write(self._mission_gen.mission)
 
-        # self.launch_file_path = os.path.join(sim_dir, 'sim.launch')
-        # with open(self.launch_file_path, 'w') as f:
-        #     config = {'mission_file' : self.mission_file_path}
-        #     f.write(scrimmage_ros.utils.generate_sim_roslaunch(config))
-
     def entity_ids(self):
         return self._mission_gen.entity_ids()
+
+    def entity_id_to_type(self, id):
+        return self._mission_gen.entity_id_to_type(id)
+
+    def options(self):
+        return self._mission_gen.options
diff --git a/src/scrimmage_ros/test/templates/nav_2d_mission.yaml b/src/scrimmage_ros/test/templates/nav_2d_mission.yaml
index 333afb1..f1c0d4b 100644
--- a/src/scrimmage_ros/test/templates/nav_2d_mission.yaml
+++ b/src/scrimmage_ros/test/templates/nav_2d_mission.yaml
@@ -15,7 +15,8 @@ mission_file:
 
 # Configuration for each entity that will be injected into the mission file
 entities:
-    - template: entity.template.xml
+    - type: car
+      template: entity.template.xml
       config: 
           id: 1
           team_id: 1
@@ -25,7 +26,8 @@ entities:
           z: 0.42
           heading: 0
           
-    - template: entity.template.xml
+    - type: car
+      template: entity.template.xml
       config: 
           id: 2
           team_id: 2
diff --git a/src/scrimmage_ros/test/templates/nav_2d_processes.yaml b/src/scrimmage_ros/test/templates/nav_2d_processes.yaml
new file mode 100644
index 0000000..8c2ad91
--- /dev/null
+++ b/src/scrimmage_ros/test/templates/nav_2d_processes.yaml
@@ -0,0 +1,33 @@
+version: "1.0"
+
+# Specify default values
+defaults:
+    terminal: gnome
+    environment:
+        some_variable: some_value
+
+# Processes that are run before entities are launched
+processes:
+    - name: roscore
+      command: roscore
+      terminal: none
+      post_delay: 1.5
+
+    - name: map_server
+      command: stdbuf -oL roslaunch scrimmage_ros map_server.launch
+      terminal: none
+      
+# Processes that are run for each entity type
+entity_processes:
+    - type: car
+      processes:
+        - name: 'entity{{ id }}'
+          command: 'stdbuf -oL roslaunch scrimmage_ros entity_nav_2d.launch team_id:=1 entity_id:={{ id }}'
+          
+      # Clean up commands run for each entity
+      clean_up:
+        - name: hello
+          command: 'echo "Goodbye, Entity {{ id }}'         
+
+# Overall clean up commands (run once)
+clean_up:
diff --git a/src/scrimmage_ros/test/test_MultiProcessLogger.py b/src/scrimmage_ros/test/test_MultiProcessLogger.py
index f329e6a..61e7f63 100644
--- a/src/scrimmage_ros/test/test_MultiProcessLogger.py
+++ b/src/scrimmage_ros/test/test_MultiProcessLogger.py
@@ -6,7 +6,6 @@
 
 import scrimmage_ros.utils as sru
 import scrimmage_ros.MultiProcessLogger as MPL
-import scrimmage_ros.SimFilesGenerator as SFG
 
 # The list of processes to pass to MultiProcessLogger
 processes = []
@@ -14,33 +13,28 @@
 mpl = MPL.MultiProcessLogger()
 
 env = os.environ.copy()
+env['PYTHONUNBUFFERED'] = '1'
 
 tmp_dir = tempfile.mkdtemp()
 
-# Generate the scrimmage mission file and simulation roslaunch file
-sfg = SFG.SimFilesGenerator('$(find scrimmage_ros)/missions/example_template/mission.yaml', tmp_dir)
-
-# Get the entity IDs from the mission.yaml file
-entity_ids = sfg.entity_ids()
-
-# Create the process that launches scrimmage and sets simulation ROS params.
 processes.append(
-    { 'command': sru.ros_launch_file(sfg.launch_file_path),
+    { 'command': 'roscore',
       'env': env,
       'console': True,
-      'file': tmp_dir + '/roslaunch.log',
+      'terminal': mpl.terminal.none,
+      'file': tmp_dir + '/roscore.log',
       'post_delay': 1.5
     }
 )
 
-for entity_id in range(1, 3):
-    args = 'team_id:=1 entity_id:=%d' % entity_id
+for id in range(1, 5):
+    cmd = 'echo "Hello, Entity %d"' % id
     processes.append(
-        { 'command': sru.ros_launch('scrimmage_ros', 'test_entity.launch', args),
+        { 'command': cmd,
           'env': env,
           'console': True,
-          'terminal': mpl.terminal.gnome,
-          'file': tmp_dir + '/entity%d/entity.log' % entity_id
+          'terminal': mpl.terminal.none,
+          'file': tmp_dir + '/entity%d/entity.log' % id
         }
     )
 
diff --git a/src/scrimmage_ros/test/test_entity_launch.py b/src/scrimmage_ros/test/test_entity_launch.py
index cd3ecbb..3cf2e87 100644
--- a/src/scrimmage_ros/test/test_entity_launch.py
+++ b/src/scrimmage_ros/test/test_entity_launch.py
@@ -14,40 +14,24 @@ def main():
         description='Runs the autonomy in HIL or SIL.')
     parser.add_argument('-s', '--sim_mission_yaml_file',
                         default='$(find scrimmage_ros)/src/scrimmage_ros/test/templates/nav_2d_mission.yaml')
-    parser.add_argument('-p', '--ros_package_name', type=str,
-                        default='scrimmage_ros',
-                        help='ROS package that contains launch file')
-    parser.add_argument('-f', '--launch_file', type=str,
-                        default='entity_nav_2d.launch',
-                        help='Launch file in ROS package')
-    parser.add_argument('-t', '--terminal', type=Terminal,
-                        choices=list(Terminal),
-                        default=Terminal.gnome)
+    parser.add_argument('-p', '--processes_yaml_file',
+                        default='$(find scrimmage_ros)/src/scrimmage_ros/test/templates/nav_2d_processes.yaml')
+    parser.add_argument('-d', '--debug', action='store_true')
 
     # Parse the arguments
     args = parser.parse_args()
 
-    # ROS launch args. {{ id }} is substituted for entity ID
-    launch_args = 'team_id:=1 entity_id:={{ id }}'
-
     # Specify a directory to hold logs and generated files
     logs_path = os.path.join(sru.user_home(), '.ros/scrimmage')
     run_dir = sru.make_get_run_dir(logs_path)
 
-    entity_launch = EntityLaunch(args.sim_mission_yaml_file, run_dir,
-                                 args.ros_package_name, args.launch_file,
-                                 launch_args, None, args.terminal)
-
-    # Append a custom ros launch file to the processes list to launch a common
-    # map server for both agents. The map server exists outside of a ROS
-    # namespace
-    entity_launch.processes.append(
-        { 'command': sru.ros_launch('scrimmage_ros', 'map_server.launch', ''),
-          'env': os.environ.copy(),
-          'console': False,
-          'terminal': Terminal.gnome
-        }
-    )
+    entity_launch = EntityLaunch(args.sim_mission_yaml_file,
+                                 args.processes_yaml_file,
+                                 run_dir, None, None)
+
+    if args.debug:
+        entity_launch.print_processes()
+        return
 
     # Run the processes. Blocking.
     entity_launch.run()
diff --git a/src/scrimmage_ros/test/test_sim_file_generation.py b/src/scrimmage_ros/test/test_sim_file_generation.py
index 692d47a..d6c6699 100644
--- a/src/scrimmage_ros/test/test_sim_file_generation.py
+++ b/src/scrimmage_ros/test/test_sim_file_generation.py
@@ -14,9 +14,3 @@
     print("==================================================================")
     with open(sfg.mission_file_path, 'r') as file:
         print(file.read())
-
-    print("==================================================================")
-    print("ROS Launch File: %s" % sfg.launch_file_path)
-    print("==================================================================")
-    with open(sfg.launch_file_path, 'r') as file:
-        print(file.read())
diff --git a/src/scrimmage_ros/utils.py b/src/scrimmage_ros/utils.py
index 026a7ff..b222956 100644
--- a/src/scrimmage_ros/utils.py
+++ b/src/scrimmage_ros/utils.py
@@ -60,7 +60,7 @@ def gnome_terminal_title(title):
     return "echo -ne \\\"\\033]0;" + title + "\\007\\\""
 
 def gnome_terminal_cmd(title, cmd, log_file):
-    return "gnome-terminal --disable-factory -x bash -c '" + cmd \
+    return "gnome-terminal --disable-factory -- bash -c '" + cmd \
         + " 2>&1 | tee " + log_file + "; exec bash'"
 
 def user_home():