diff --git a/mosfet/job.py b/mosfet/job.py
index b6676cd..9b10de3 100644
--- a/mosfet/job.py
+++ b/mosfet/job.py
@@ -82,7 +82,11 @@ class LegacyJobStates:
             if m.state == m.idle:
                 continue
             if m.state != m.done:
-                m.run()
+                self.active_machine = m
+                try:
+                    m.run()
+                finally:
+                    self.active_machine = None
                 return
         # if we went through them all
         for m in machines:
@@ -256,6 +260,7 @@ class LegacyJobStates:
 
     def __init__(self, global_state):
         self.g = global_state
+        self.active_machine = None
 
         self.init_machines()
         self.state = self.idle
@@ -281,6 +286,7 @@ class JobStates(LegacyJobStates):
         self.eat_food_states = eat_food.EatFoodStates(global_state)
         self.check_threats_states = check_threats.CheckThreatsStates(
             global_state)
+        self.active_machine = None
         self.state = self.idle
 
     def farm_wood(self):
@@ -356,4 +362,5 @@ class JobStates(LegacyJobStates):
         self.check_threats_states.external_safety = False
         self.gather_crop_states.active_section_anchor = None
         self.gather_crop_states.completed_crops = 0
+        self.active_machine = None
         self.state = self.idle
diff --git a/mosfet/jobs/gather_crop.py b/mosfet/jobs/gather_crop.py
index 3b3bc2c..1beac21 100644
--- a/mosfet/jobs/gather_crop.py
+++ b/mosfet/jobs/gather_crop.py
@@ -92,10 +92,12 @@ class GatherCropStates:
             blocks.MATURE_BEETROOT_ID,
         ]
 
-        candidates = w.find_blocks_indexed(p, mature_crops, 50)
+        candidates = w.filter_work_positions(
+            w.find_blocks_indexed(p, mature_crops, 50))
         crop_ids = (blocks.WHEAT_IDS | blocks.POTATO_IDS |
                     blocks.CARROT_IDS | blocks.BEETROOT_IDS)
-        crop_positions = w.find_blocks_indexed(p, crop_ids, 50)
+        crop_positions = w.filter_work_positions(
+            w.find_blocks_indexed(p, crop_ids, 50))
         crop_types = {
             position: blocks.BLOCKS.get(w.block_at(*position))
             for position in crop_positions
diff --git a/mosfet/jobs/gather_sand.py b/mosfet/jobs/gather_sand.py
index 1d7d251..9052e31 100644
--- a/mosfet/jobs/gather_sand.py
+++ b/mosfet/jobs/gather_sand.py
@@ -61,12 +61,13 @@ class GatherSandStates:
         head = utils.padd(p, path.BLOCK_ABOVE)
 
         for sand in w.find_sand(self.slice, 2, p):
-            if sand not in self.bad_sand:
+            if (sand not in self.bad_sand and
+                    w.work_position_allowed(sand)):
                 print('Found sand:', sand)
                 break
         else: # for
-            print('No good sands left, aborting.')
-            self.state = self.cleanup
+            print('No in-bounds sand left in this slice; trying another.')
+            self.state = self.find_new_slice
             return
 
         self.sand = sand
diff --git a/mosfet/jobs/gather_wart.py b/mosfet/jobs/gather_wart.py
index 3a3eb98..4405ced 100644
--- a/mosfet/jobs/gather_wart.py
+++ b/mosfet/jobs/gather_wart.py
@@ -30,7 +30,8 @@ class GatherWartStates:
 
         mature_wart = max(blocks.NETHERWART_IDS)
         for wart in w.find_blocks_3d(p, [mature_wart], 50, 20, True):
-            if wart not in self.bad_warts:
+            if (wart not in self.bad_warts and
+                    w.work_position_allowed(wart)):
                 break
         else: # for
             print('No good warts left, aborting.')
diff --git a/mosfet/jobs/gather_wood.py b/mosfet/jobs/gather_wood.py
index 48142a2..9637462 100644
--- a/mosfet/jobs/gather_wood.py
+++ b/mosfet/jobs/gather_wood.py
@@ -30,10 +30,11 @@ class GatherWoodStates:
         w = self.g.world
         p = utils.pint(self.g.pos)
 
-        for tree in w.find_trees(p, 100):
-            print('Found tree:', tree)
+        trees = w.filter_work_positions(w.find_trees(p, 100))
+        for tree in trees:
             if tree in self.bad_trees:
                 continue
+            print('Found tree:', tree)
             tree_type = blocks.BLOCKS[w.block_at(*tree)].replace('_log', '')
             if items.get_sapling_id(tree_type) is None:
                 print('No plantable sapling for', tree_type, '- skipping')
@@ -53,7 +54,10 @@ class GatherWoodStates:
 
     def find_openings(self):
         w = self.g.world
-        self.openings = w.find_tree_openings(self.tree)
+        self.openings = [
+            opening for opening in w.find_tree_openings(self.tree)
+            if w.work_position_allowed(opening)
+        ]
         self.state = self.choose_opening
 
     def choose_opening(self):
diff --git a/mosfet/jobs/grab_sapling.py b/mosfet/jobs/grab_sapling.py
index 197fee6..3cbdad6 100644
--- a/mosfet/jobs/grab_sapling.py
+++ b/mosfet/jobs/grab_sapling.py
@@ -44,6 +44,8 @@ class GrabSaplingStates:
 
             if s.entity_id in self.eid_blacklist:
                 continue
+            if not w.work_position_allowed(s_pos):
+                continue
 
             # skip if the sapling is floating
             if self.g.chunks.get_block_at(*check) in blocks.LEAF_IDS | {0}:
diff --git a/mosfet/jobs/plant_tree.py b/mosfet/jobs/plant_tree.py
index 199eb69..95a32c3 100644
--- a/mosfet/jobs/plant_tree.py
+++ b/mosfet/jobs/plant_tree.py
@@ -80,6 +80,8 @@ class PlantTreeStates:
         p = utils.pint(self.g.pos)
 
         for opening in w.find_tree_openings(p)[::-1]:
+            if not w.work_position_allowed(opening):
+                continue
             print('trying sapling opening', opening)
             navpath = w.path_to_place(p, opening)
             if navpath:
diff --git a/mosfet/world.py b/mosfet/world.py
index c38cf87..afa5ead 100644
--- a/mosfet/world.py
+++ b/mosfet/world.py
@@ -76,6 +76,113 @@ class World:
         result.sort(key=lambda sign: utils.phyp(center, sign['position']))
         return result
 
+    def sign_policies(self, bot_name, distance=64):
+        """Parse sign policies addressed to this bot or its numbered group."""
+        bot_name = str(bot_name).casefold()
+        group_name = (bot_name[:-1] if len(bot_name) > 1 and
+                      bot_name[-1] in '123' else None)
+        addresses = {bot_name}
+        if group_name:
+            addresses.add(group_name)
+
+        center = utils.pint(self.g.pos)
+        policies = []
+        active_sign_position = None
+        for sign in self.find_signs(center, distance):
+            lines = [line.strip() for line in sign['lines'] if line.strip()]
+            if not lines:
+                continue
+            first = lines[0].split(maxsplit=1)
+            address = first[0].rstrip(':,').casefold()
+            if address not in addresses:
+                continue
+            directives = ([first[1]] if len(first) > 1 else []) + lines[1:]
+            text = ' '.join(directives).casefold()
+            sign_policies = []
+            for match in re.finditer(
+                    r'\bstay\s+within\s*(\d+)(?:\s+(squares?|circle))?\b',
+                    text):
+                shape = match.group(2) or 'circle'
+                if shape == 'squares':
+                    shape = 'square'
+                sign_policies.append({
+                    'position': sign['position'],
+                    'distance': int(match.group(1)),
+                    'shape': shape,
+                    'side': sign['side'],
+                })
+            if not sign_policies:
+                continue
+            if active_sign_position is None:
+                # The nearest addressed policy sign overrides farther signs.
+                active_sign_position = sign['position']
+            if sign['position'] == active_sign_position:
+                policies.extend(sign_policies)
+        return policies
+
+    def _active_work_policies(self):
+        job = self.g.get('job')
+        machine = getattr(job, 'active_machine', None) if job else None
+        if machine is None:
+            return []
+        support_machines = (
+            'grab_supplies_states', 'sleep_with_bed_states',
+            'eat_food_states', 'cache_items_states',
+            'check_threats_states',
+        )
+        if any(machine is getattr(job, name, None)
+               for name in support_machines):
+            return []
+        return self.sign_policies(self.g.get('name', ''))
+
+    @staticmethod
+    def _sign_policy_distance(position, policy):
+        # Work zones are horizontal; crop height or terrain elevation does not
+        # consume the sign's radius.
+        dx = abs(position[0] - policy['position'][0])
+        dz = abs(position[2] - policy['position'][2])
+        if policy['shape'] == 'square':
+            return max(dx, dz)
+        return utils.hypot(dx, dz)
+
+    @classmethod
+    def _inside_sign_policy(cls, position, policy):
+        return cls._sign_policy_distance(position, policy) <= policy['distance']
+
+    def work_position_allowed(self, position):
+        """Whether a work target satisfies all currently active sign rules."""
+        return all(self._inside_sign_policy(position, policy)
+                   for policy in self._active_work_policies())
+
+    def filter_work_positions(self, positions):
+        """Filter a candidate set once against the active sign policies."""
+        policies = self._active_work_policies()
+        positions = list(positions)
+        if not policies:
+            return positions
+        return [position for position in positions
+                if all(self._inside_sign_policy(position, policy)
+                       for policy in policies)]
+
+    @classmethod
+    def _path_allowed_by_sign(cls, points, policy):
+        distances = [cls._sign_policy_distance(point, policy)
+                     for point in points]
+        radius = policy['distance']
+        if distances[0] <= radius:
+            return all(distance <= radius for distance in distances)
+
+        # If the bot starts just outside a newly read boundary, let it return
+        # without allowing it to travel farther away from that sign.
+        start_distance = distances[0]
+        entered = False
+        for distance in distances[1:]:
+            if distance > start_distance or (entered and distance > radius):
+                return False
+            if distance <= radius:
+                entered = True
+        return entered
+
     def check_air_column(self, pos, distance):
         for i in range(distance):
             check = utils.padd(pos, (0, i, 0))
@@ -194,11 +301,23 @@ class World:
         maze_solver = path.Pathfinder(self.g)
 
         try:
-            s = maze_solver.astar(start, place)
-            return list(s) if s else None
+            solution = maze_solver.astar(start, place)
+            if not solution:
+                return None
+            navpath = list(solution)
         except path.AStarTimeout:
             return None
 
+        policies = self._active_work_policies()
+        points = [tuple(start)] + [tuple(point) for point in navpath]
+        for policy in policies:
+            if not self._path_allowed_by_sign(points, policy):
+                print('[sign policy] rejected work path outside {}-block {} '
+                      'around {}'.format(policy['distance'], policy['shape'],
+                                         policy['position']), flush=True)
+                return None
+        return navpath
+
     def path_to_place_faked(self, start, place):
         # same as above, but adds a fake block below and air before pathfinding
         # so that the pathfinder can actually make it to the block
diff --git a/tests/test_gather_wood.py b/tests/test_gather_wood.py
index 6facc3f..461ac31 100644
--- a/tests/test_gather_wood.py
+++ b/tests/test_gather_wood.py
@@ -36,6 +36,14 @@ class GatherWoodPortTests(unittest.TestCase):
             def find_trees(self, _position, _distance):
                 return [(0, 64, 0), (3, 64, 0)]
 
+            @staticmethod
+            def work_position_allowed(_position):
+                return True
+
+            def filter_work_positions(self, positions):
+                return [position for position in positions
+                        if self.work_position_allowed(position)]
+
             def block_at(self, x, y, z):
                 return (blocks.MCD_BLOCKS['crimson_stem']['minStateId']
                         if x == 0 else
diff --git a/tests/test_sign_work_targets.py b/tests/test_sign_work_targets.py
new file mode 100644
index 0000000..926e833
--- /dev/null
+++ b/tests/test_sign_work_targets.py
@@ -0,0 +1,68 @@
+import unittest
+from munch import Munch
+
+from mosfet.info import blocks
+from mosfet.jobs.gather_crop import GatherCropStates
+from mosfet.jobs.gather_wood import GatherWoodStates
+
+
+class SignWorkTargetTests(unittest.TestCase):
+    def test_crop_search_filters_out_of_bounds_candidates_before_navigation(self):
+        outside = (10, 64, 0)
+        mature_wheat = blocks.MATURE_WHEAT_ID
+        crop_state = blocks.MCD_BLOCKS['wheat']['minStateId']
+
+        class FakeWorld:
+            def find_blocks_indexed(self, _center, _block_ids, _distance):
+                return [outside]
+
+            @staticmethod
+            def work_position_allowed(position):
+                return position != outside
+
+            def filter_work_positions(self, positions):
+                return [position for position in positions
+                        if self.work_position_allowed(position)]
+
+            @staticmethod
+            def block_at(*_position):
+                return crop_state
+
+        state = GatherCropStates(Munch(world=FakeWorld(), pos=(0, 64, 0)))
+        state.find_new_crop()
+
+        self.assertIs(state.state.__func__, state.wait_for_crops.__func__)
+        self.assertEqual(state.bad_crops, [])
+
+    def test_tree_search_skips_out_of_bounds_tree_without_blacklisting_it(self):
+        outside = (10, 64, 0)
+        inside = (2, 64, 0)
+        oak_log = blocks.MCD_BLOCKS['oak_log']['minStateId']
+
+        class FakeWorld:
+            @staticmethod
+            def find_trees(_center, _distance):
+                return [outside, inside]
+
+            @staticmethod
+            def work_position_allowed(position):
+                return position != outside
+
+            def filter_work_positions(self, positions):
+                return [position for position in positions
+                        if self.work_position_allowed(position)]
+
+            @staticmethod
+            def block_at(*_position):
+                return oak_log
+
+        state = GatherWoodStates(Munch(world=FakeWorld(), pos=(0, 64, 0)))
+        state.find_new_tree()
+
+        self.assertEqual(state.tree, inside)
+        self.assertEqual(state.type, 'oak')
+        self.assertEqual(state.bad_trees, [])
+
+
+if __name__ == '__main__':
+    unittest.main()
diff --git a/tests/test_signs.py b/tests/test_signs.py
index 0576a28..39d1605 100644
--- a/tests/test_signs.py
+++ b/tests/test_signs.py
@@ -1,4 +1,5 @@
 import unittest
+from unittest.mock import patch
 from munch import Munch
 
 from mosfet.commands import Commands
@@ -44,6 +45,88 @@ class SignReadingTests(unittest.TestCase):
         signs = World(Munch(chunks=chunks)).find_signs((4, 65, -2), 1)
         self.assertEqual(signs[0]['lines'], ('Farm', '', '', ''))
 
+    def test_group_and_individual_sign_addresses(self):
+        group_world = World(Munch(chunks=Munch(block_entities={
+            (0, 64, 0): {'data': {'front_text': {'messages': [
+                'mosfet', 'stay within25', 'square', '',
+            ]}}},
+        }), pos=(0, 64, 0)))
+        for bot_name in ('mosfet1', 'mosfet2', 'mosfet3'):
+            self.assertEqual([p['shape'] for p in
+                              group_world.sign_policies(bot_name)], ['square'])
+        self.assertEqual(group_world.sign_policies('mosfet4'), [])
+
+        individual_world = World(Munch(chunks=Munch(block_entities={
+            (1, 64, 0): {'data': {'front_text': {'messages': [
+                'mosfet2', 'stay within 10 circle', '', '',
+            ]}}},
+        }), pos=(1, 64, 0)))
+        self.assertEqual([p['shape'] for p in
+                          individual_world.sign_policies('mosfet2')], ['circle'])
+        self.assertEqual(individual_world.sign_policies('mosfet1'), [])
+
+    def test_nearest_sign_policy_overrides_farther_matching_sign(self):
+        chunks = Munch(block_entities={
+            (-138, 71, -268): {'data': {'front_text': {'messages': [
+                'mosfet1', 'stay within 25 square', '', '',
+            ]}}},
+            (-158, 71, -248): {'data': {'front_text': {'messages': [
+                'mosfet1', 'stay within 6 squares', '', '',
+            ]}}},
+        })
+        world = World(Munch(chunks=chunks, pos=(-158, 71, -248)))
+        self.assertEqual(world.sign_policies('mosfet1'), [{
+            'position': (-158, 71, -248), 'distance': 6,
+            'shape': 'square', 'side': 'front',
+        }])
+
+    def test_work_paths_obey_sign_boundary_but_cache_paths_do_not(self):
+        sign_data = {'front_text': {'messages': [
+            'mosfet1', 'stay within 25 square', '', '',
+        ]}}
+        chunks = Munch(block_entities={(0, 64, 0): {'data': sign_data}})
+        work_machine = object()
+        cache_machine = object()
+        job = Munch(active_machine=work_machine,
+                    cache_items_states=cache_machine)
+        world = World(Munch(chunks=chunks, job=job, name='mosfet1',
+                            pos=(0, 64, 0)))
+
+        class FixedPathfinder:
+            @staticmethod
+            def astar(_start, _place):
+                return [(0, 64, 0), (20, 64, 0), (30, 64, 0)]
+
+        with patch('mosfet.world.path.Pathfinder', return_value=FixedPathfinder()):
+            self.assertIsNone(world.path_to_place((0, 64, 0), (30, 64, 0)))
+            job.active_machine = cache_machine
+            self.assertEqual(world.path_to_place(
+                (0, 64, 0), (30, 64, 0)),
+                [(0, 64, 0), (20, 64, 0), (30, 64, 0)])
+
+        policy = {'position': (0, 64, 0), 'distance': 25, 'shape': 'square'}
+        self.assertTrue(World._path_allowed_by_sign(
+            [(30, 64, 0), (27, 64, 0), (24, 64, 0)], policy))
+        self.assertFalse(World._path_allowed_by_sign(
+            [(30, 64, 0), (32, 64, 0), (24, 64, 0)], policy))
+
+        six_square = {'position': (-158, 71, -248),
+                      'distance': 6, 'shape': 'square'}
+        six_circle = dict(six_square, shape='circle')
+        crop = (-162, 68, -247)
+        self.assertEqual(World._sign_policy_distance(crop, six_square), 4)
+        self.assertAlmostEqual(World._sign_policy_distance(crop, six_circle),
+                               (17 ** 0.5))
+
+        four_square = {'position': (0, 64, 0),
+                       'distance': 4, 'shape': 'square'}
+        self.assertEqual(World._sign_policy_distance((4, 70, 4), four_square), 4)
+        self.assertTrue(World._inside_sign_policy((4, 70, 4), four_square))
+        self.assertFalse(World._inside_sign_policy((5, 64, 4), four_square))
+        same_xz_far_y = (-158, -20, -248)
+        self.assertEqual(
+            World._sign_policy_distance(same_xz_far_y, six_square), 0)
+
     def test_signs_command_replies_with_nearby_text(self):
         class FakeChat:
             def __init__(self):