diff --git a/pillar_tool/db/migrations/versions/2026_02_14_2335-a5848dcca950_fixed_errors_in_database_schema.py b/pillar_tool/db/migrations/versions/2026_02_14_2335-a5848dcca950_fixed_errors_in_database_schema.py
new file mode 100644
index 0000000..f25a9f8
--- /dev/null
+++ b/pillar_tool/db/migrations/versions/2026_02_14_2335-a5848dcca950_fixed_errors_in_database_schema.py
@@ -0,0 +1,32 @@
+"""fixed errors in database schema
+
+Revision ID: a5848dcca950
+Revises: dd573f631ee4
+Create Date: 2026-02-14 23:35:07.882896
+
+"""
+from typing import Sequence, Union
+
+from alembic import op
+import sqlalchemy as sa
+
+
+# revision identifiers, used by Alembic.
+revision: str = 'a5848dcca950'
+down_revision: Union[str, Sequence[str], None] = 'dd573f631ee4'
+branch_labels: Union[str, Sequence[str], None] = None
+depends_on: Union[str, Sequence[str], None] = None
+
+
+def upgrade() -> None:
+    """Upgrade schema."""
+    # ### commands auto generated by Alembic - please adjust! ###
+    pass
+    # ### end Alembic commands ###
+
+
+def downgrade() -> None:
+    """Downgrade schema."""
+    # ### commands auto generated by Alembic - please adjust! ###
+    pass
+    # ### end Alembic commands ###
diff --git a/pillar_tool/db/migrations/versions/2026_02_14_2337-58c2a8e7c302_import_top_data.py b/pillar_tool/db/migrations/versions/2026_02_14_2337-58c2a8e7c302_import_top_data.py
new file mode 100644
index 0000000..f55ef4f
--- /dev/null
+++ b/pillar_tool/db/migrations/versions/2026_02_14_2337-58c2a8e7c302_import_top_data.py
@@ -0,0 +1,65 @@
+"""import top_data
+
+Revision ID: 58c2a8e7c302
+Revises: a5848dcca950
+Create Date: 2026-02-14 23:37:42.194003
+
+"""
+from typing import Sequence, Union
+
+from alembic import op
+import sqlalchemy as sa
+
+
+# revision identifiers, used by Alembic.
+revision: str = '58c2a8e7c302'
+down_revision: Union[str, Sequence[str], None] = 'a5848dcca950'
+branch_labels: Union[str, Sequence[str], None] = None
+depends_on: Union[str, Sequence[str], None] = None
+
+
+def upgrade() -> None:
+    """Upgrade schema."""
+    # ### commands auto generated by Alembic - please adjust! ###
+    op.create_table('pillar_tool_environment',
+    sa.Column('id', sa.UUID(), nullable=False),
+    sa.Column('name', sa.String(), nullable=False),
+    sa.PrimaryKeyConstraint('id'),
+    sa.UniqueConstraint('name', name='pillar_tool_unique_environment_unique_name')
+    )
+    op.create_table('pillar_tool_state',
+    sa.Column('id', sa.UUID(), nullable=False),
+    sa.Column('name', sa.String(), nullable=False),
+    sa.PrimaryKeyConstraint('id'),
+    sa.UniqueConstraint('name', name='pillar_tool_unique_state_unique_name')
+    )
+    op.create_table('pillar_tool_environment_assignment',
+    sa.Column('environment_id', sa.UUID(), nullable=False),
+    sa.Column('host_id', sa.UUID(), nullable=False),
+    sa.ForeignKeyConstraint(['environment_id'], ['pillar_tool_environment.id'], ),
+    sa.ForeignKeyConstraint(['host_id'], ['pillar_tool_host.id'], ),
+    sa.PrimaryKeyConstraint('environment_id', 'host_id'),
+    sa.UniqueConstraint('environment_id', 'host_id', name='pillar_tool_unique_environment_assignment')
+    )
+    op.create_table('pillar_tool_state_assignment',
+    sa.Column('id', sa.UUID(), nullable=False),
+    sa.Column('environment_id', sa.UUID(), nullable=False),
+    sa.Column('state_id', sa.UUID(), nullable=False),
+    sa.Column('host_id', sa.UUID(), nullable=False),
+    sa.ForeignKeyConstraint(['environment_id'], ['pillar_tool_environment.id'], ),
+    sa.ForeignKeyConstraint(['host_id'], ['pillar_tool_host.id'], ),
+    sa.ForeignKeyConstraint(['state_id'], ['pillar_tool_state.id'], ),
+    sa.PrimaryKeyConstraint('id'),
+    sa.UniqueConstraint('environment_id', 'state_id', 'host_id', name='pillar_tool_state_assignment_unique_env_state_host')
+    )
+    # ### end Alembic commands ###
+
+
+def downgrade() -> None:
+    """Downgrade schema."""
+    # ### commands auto generated by Alembic - please adjust! ###
+    op.drop_table('pillar_tool_state_assignment')
+    op.drop_table('pillar_tool_environment_assignment')
+    op.drop_table('pillar_tool_state')
+    op.drop_table('pillar_tool_environment')
+    # ### end Alembic commands ###
diff --git a/pillar_tool/db/models/__init__.py b/pillar_tool/db/models/__init__.py
index 95ad4eb..68112e7 100644
--- a/pillar_tool/db/models/__init__.py
+++ b/pillar_tool/db/models/__init__.py
@@ -1,2 +1,3 @@
 from .user import *
-from .pillar_data import *
\ No newline at end of file
+from .pillar_data import *
+from .top_data import *
\ No newline at end of file
diff --git a/pillar_tool/db/models/top_data.py b/pillar_tool/db/models/top_data.py
index 88174b6..d9d67cf 100644
--- a/pillar_tool/db/models/top_data.py
+++ b/pillar_tool/db/models/top_data.py
@@ -11,18 +11,18 @@ class Environment(Base):
     name = Column(String, nullable=False)
 
     __table_args__ = (
-        UniqueConstraint('name', name="pillar_tool_unique_environment_unique_name")
+        UniqueConstraint('name', name="pillar_tool_unique_environment_unique_name"),
     )
 
 
 class EnvironmentAssignment(Base):
     __tablename__ = "pillar_tool_environment_assignment"
 
-    environment_id = Column(UUID, ForeignKey("pillar_tool_environment.id"), nullable=False)
-    host_id = Column(UUID, ForeignKey("pillar_tool_host.id"), nullable=False)
+    environment_id = Column(UUID, ForeignKey("pillar_tool_environment.id"), nullable=False, primary_key=True)
+    host_id = Column(UUID, ForeignKey("pillar_tool_host.id"), nullable=False, primary_key=True)
 
     __table_args__ = (
-        UniqueConstraint('environment_id', 'host_id', name="pillar_tool_unique_environment_assignment")
+        UniqueConstraint('environment_id', 'host_id', name="pillar_tool_unique_environment_assignment"),
     )
 
 
@@ -33,7 +33,7 @@ class State(Base):
     name = Column(String, nullable=False)
 
     __table_args__ = (
-        UniqueConstraint('name', name="pillar_tool_unique_state_unique_name")
+        UniqueConstraint('name', name="pillar_tool_unique_state_unique_name"),
     )
 
 
diff --git a/pillar_tool/main.py b/pillar_tool/main.py
index f12b4f7..2cbd018 100644
--- a/pillar_tool/main.py
+++ b/pillar_tool/main.py
@@ -25,6 +25,7 @@ from pillar_tool.db.database import run_db_migrations
 # import all the routers
 from pillar_tool.routers.host import router as host_router
 from pillar_tool.routers.hostgroup import router as hostgroup_router
+from pillar_tool.routers.environment import router as environment_router
 
 # run any pending migrations
 run_db_migrations()
@@ -70,6 +71,7 @@ app.exception_handler(Exception)(on_general_error)
 # Setup the api router
 app.include_router(host_router)
 app.include_router(hostgroup_router)
+app.include_router(environment_router)
 
 @app.get("/")
 async def root():
diff --git a/pillar_tool/ptcli/cli/environment.py b/pillar_tool/ptcli/cli/environment.py
index f839b60..b3f0c97 100644
--- a/pillar_tool/ptcli/cli/environment.py
+++ b/pillar_tool/ptcli/cli/environment.py
@@ -2,8 +2,95 @@ import click
 import requests
 
 from .cli_main import main, auth_header, base_url
+from pillar_tool.util.validation import split_and_validate_path
 
 
 @main.group("environment")
 def environment():
-    pass
\ No newline at end of file
+    pass
+
+
+@environment.command("list")
+def environment_list():
+    """List all environments."""
+    click.echo("Listing known environments...")
+    try:
+        response = requests.get(f'{base_url()}/environment', headers=auth_header())
+        response.raise_for_status()
+
+        click.echo("Environments:")
+        for env in response.json():
+            click.echo(f"  - {env}")
+    except requests.exceptions.HTTPError as e:
+        raise click.ClickException(f"Failed to list environments:\n{e}")
+
+
+@environment.command("show")
+@click.argument("name")
+def environment_show(name: str):
+    """Show details of a specific environment by name."""
+    click.echo(f"Showing environment '{name}'...")
+    try:
+        # Validate name format before making request
+        if not split_and_validate_path.__module__ or True:  # Using environment-specific validation
+            from pillar_tool.util.validation import validate_environment_name
+            if not validate_environment_name(name):
+                raise click.ClickException(
+                    "Invalid environment name. Use only alphanumeric, underscore or dash characters.")
+
+        response = requests.get(f'{base_url()}/environment/{name}', headers=auth_header())
+        response.raise_for_status()
+
+        env_data = response.json()
+        click.echo(f"Environment: {env_data['environment']}")
+        click.echo(f"Hosts assigned: {env_data['host_count']}")
+    except requests.exceptions.HTTPError as e:
+        raise click.ClickException(f"Failed to show environment:\n{e}")
+
+
+@environment.command("create")
+@click.argument("name")
+def environment_create(name: str):
+    """Create a new environment."""
+    click.echo(f"Creating environment '{name}'...")
+    try:
+        from pillar_tool.util.validation import validate_environment_name
+        if not validate_environment_name(name):
+            raise click.ClickException(
+                "Invalid environment name. Use only alphanumeric, underscore or dash characters.")
+
+        # No body data needed for environment creation
+        response = requests.post(f'{base_url()}/environment/{name}', headers=auth_header())
+        response.raise_for_status()
+
+        click.echo(f"Environment '{name}' created successfully.")
+    except requests.exceptions.HTTPError as e:
+        raise click.ClickException(f"Failed to create environment:\n{e}")
+
+
+@environment.command("delete")
+@click.argument("name")
+def environment_delete(name: str):
+    """Delete an environment by name."""
+    click.echo(f"Deleting environment '{name}'...")
+    try:
+        from pillar_tool.util.validation import validate_environment_name
+        if not validate_environment_name(name):
+            raise click.ClickException(
+                "Invalid environment name. Use only alphanumeric, underscore or dash characters.")
+
+        response = requests.delete(f'{base_url()}/environment/{name}', headers=auth_header())
+        response.raise_for_status()
+
+        click.echo(f"Environment '{name}' deleted successfully.")
+    except requests.exceptions.HTTPError as e:
+        if e.response is not None and e.response.status_code == 409:
+            conflict_data = e.response.json() if e.response.content else {}
+            hosts_list = conflict_data.get('assigned_hosts', [])
+            raise click.ClickException(
+                f"Failed to delete environment:\n"
+                f"{conflict_data.get('message', 'Environment has assigned hosts')}\n"
+                f"Assigned hosts: {', '.join(hosts_list) if hosts_list else 'none'}"
+            )
+        else:
+            raise click.ClickException(f"Failed to delete environment:\n{e}")
\ No newline at end of file
diff --git a/pillar_tool/routers/environment.py b/pillar_tool/routers/environment.py
index e69de29..9825b36 100644
--- a/pillar_tool/routers/environment.py
+++ b/pillar_tool/routers/environment.py
@@ -0,0 +1,179 @@
+import uuid
+
+
+from sqlalchemy import select, insert, bindparam, delete
+from sqlalchemy.orm import Session
+from starlette.exceptions import HTTPException
+from starlette.requests import Request
+from fastapi import APIRouter, Query, Depends
+from starlette.responses import JSONResponse
+
+from pillar_tool.db import Host
+from pillar_tool.db.models.top_data import Environment, EnvironmentAssignment
+from pillar_tool.schemas import HostgroupParams, get_hostgroup_params_from_query, get_model_from_query
+from pillar_tool.util.validation import split_and_validate_path, validate_environment_name
+
+router = APIRouter(
+    prefix="/environment",
+    tags=["environment"],
+)
+
+
+@router.get("")
+def environments_get(req: Request):
+    """
+    Retrieve all environments.
+
+    Fetches and returns a list of environment names from the database.
+
+    Returns:
+        JSONResponse: A JSON response with status code 200 containing a list of environment names (strings).
+    """
+    db: Session = req.state.db
+
+    result = db.execute(select(Environment)).fetchall()
+    environments: list[Environment] = list(map(lambda x: x[0], result))
+
+    return JSONResponse(status_code=200, content=[env.name for env in environments])
+
+
+@router.get("/{name}")
+def environment_get(req: Request, name: str):
+    """
+    Retrieve a specific environment by name.
+
+    Fetches and returns details of the specified environment.
+    Returns 404 if no such environment exists.
+
+    Args:
+        req (Request): The incoming request object.
+        name (str): The name of the environment to retrieve.
+
+    Returns:
+        JSONResponse: A JSON response with status code 200 and the environment details on success,
+                      or 404 if not found.
+    """
+    db: Session = req.state.db
+
+    # Validate name before query
+    if not validate_environment_name(name):
+        raise HTTPException(status_code=400, detail="Invalid environment name format")
+
+    stmt = select(Environment).where(Environment.name == name)
+    result = db.execute(stmt).fetchall()
+
+    if len(result) == 0:
+        raise HTTPException(status_code=404, detail="No such environment exists")
+
+    assert len(result) == 1
+
+    env: Environment = result[0][0]
+
+    # Get assigned hosts count as an example of additional info
+    hosts_stmt = select(Host).join(EnvironmentAssignment, Host.id == EnvironmentAssignment.host_id)\
+                              .where(EnvironmentAssignment.environment_id == env.id)
+    hosts_count = db.execute(hosts_stmt).fetchall().__len__()
+
+    return JSONResponse(status_code=200, content={
+        'environment': env.name,
+        'host_count': hosts_count
+    })
+
+
+@router.post("/{name}")
+def environment_create(req: Request, name: str):
+    """
+    Create a new environment.
+
+    Creates a new environment record in the database with the provided parameters.
+
+    Args:
+        req (Request): The incoming request object.
+        name (str): The name of the environment (must be unique).
+
+    Returns:
+        JSONResponse: A JSON response with status code 201 on success,
+                      or appropriate error codes (e.g., 409 if already exists, 400 for invalid format).
+    """
+    db = req.state.db
+
+    # Validate name format
+    if not validate_environment_name(name):
+        raise HTTPException(status_code=400,
+                            detail="Invalid environment name. Use only alphanumeric, underscore or dash characters.")
+
+    # Check if environment already exists
+    stmt_check = select(Environment).where(Environment.name == name)
+    existing = db.execute(stmt_check).fetchall()
+
+    if len(existing) > 0:
+        raise HTTPException(status_code=409, detail="Environment already exists")
+
+    new_id = uuid.uuid4()
+    db.execute(insert(Environment).values(id=new_id, name=name))
+
+    return JSONResponse(status_code=201, content={
+        'id': str(new_id),
+        'name': name
+    })
+
+
+@router.delete("/{name}")
+def environment_delete(req: Request, name: str):
+    """
+    Delete an environment by name.
+
+    Deletes the specified environment from the database.
+    Returns 409 if hosts are still assigned to this environment.
+    Returns 404 if no such environment exists.
+
+    Args:
+        req (Request): The incoming request object.
+        name (str): The name of the environment to delete.
+
+    Returns:
+        JSONResponse: A JSON response with status code 204 on successful deletion,
+                      or appropriate error codes for conflicts or not found.
+    """
+    db = req.state.db
+
+    # Validate name format
+    if not validate_environment_name(name):
+        raise HTTPException(status_code=400, detail="Invalid environment name format")
+
+    stmt = select(Environment).where(Environment.name == name)
+    result = db.execute(stmt).fetchall()
+
+    if len(result) == 0:
+        raise HTTPException(status_code=404, detail="No such environment exists")
+
+    assert len(result) == 1
+
+    env: Environment = result[0][0]
+
+    # Check for assigned hosts before deleting
+    assignments_stmt = select(EnvironmentAssignment).where(
+        EnvironmentAssignment.environment_id == env.id
+    )
+    assignments = db.execute(assignments_stmt).fetchall()
+
+    if len(assignments) > 0:
+        host_ids_stmt = select(EnvironmentAssignment.host_id).where(
+            EnvironmentAssignment.environment_id == env.id
+        )
+        host_ids = [row[0] for row in db.execute(host_ids_stmt).fetchall()]
+
+        # Get host names (could optimize this)
+        hosts_stmt = select(Host).where(Host.id.in_(host_ids))
+        hosts: list[Host] = list(map(lambda x: x[0], db.execute(hosts_stmt).fetchall()))
+
+        return JSONResponse(status_code=409, content={
+            'message': "Cannot delete an environment that still has hosts assigned",
+            'assigned_hosts': [h.name for h in hosts]
+        })
+
+    # Delete the environment
+    db.execute(delete(Environment).where(Environment.id == env.id))
+
+    return JSONResponse(status_code=204, content={})
+
diff --git a/pillar_tool/util/validation.py b/pillar_tool/util/validation.py
index a152351..af5e4cb 100644
--- a/pillar_tool/util/validation.py
+++ b/pillar_tool/util/validation.py
@@ -4,6 +4,26 @@ import re
 PATH_REGEX = re.compile(r'^[a-zA-Z_-][a-zA-Z0-9_-]*$')
 FQDN_REGEX = re.compile(r'^([a-zA-Z0-9.-]+\.)+[a-zA-Z]{2,}$')
 
+ENV_NAME_REGEX = re.compile(r'^[a-zA-Z0-9_-]+$')
+
+
+# TODO: improve doc comment for this function
+def validate_environment_name(name: str) -> bool:
+    """
+    Validates an environment name.
+
+    Args:
+        name: The environment name to validate (e.g., "production", "dev_env")
+
+    Returns:
+        True if the name contains only alphanumeric characters, underscores, or dashes.
+        False otherwise.
+
+    Note:
+        Environment names cannot be empty and must match the pattern [a-zA-Z0-9_-]+
+    """
+    return bool(ENV_NAME_REGEX.match(name))
+
 
 def validate_fqdn(fqdn: str) -> bool:
     """